Workhorse Diagnostic Assistance

Posted by Alan 10/06/2016 46 Comment(s)

We offer Technical Assistance for your Workhorse RV Chassis. This technical support includes Drivability, Auto Park Brake, Steering and Handling, and Electrical issues. Our staff is experienced and helpful for repair shops around the country, or RV owners that just need a little guidance. We also offer a full range of Genuine and Aftermarket parts for the Workhorse Chassis through our parts distribution site www.urvp.com. Please leave us a question or feedback about what we have done or can do to help you.

46 Comment(s)

Steve Barka:
01/27/2017, 04:57:40 PM, Workhorse 8.1L gas 2004.
Reply

Starter won't engage when temperature is below 40 degrees. Battery tests good, cleaned cable connections, tried auxiliary battery switch, clicked but no help. Jumped starter solenoid and started right up. ???

Alan:
01/30/2017, 03:26:34 PM

Steve, That is a good one, I would test at the starter relay in the under hood fuse block, check and see with the relay removed to see if you have a ground being provided to pin 85 or 86 when the key is turned to the crank position. If you do see a switched ground at one of those pins, then see if you have 12 volts at the other pin either 85 or 86 when the key is in the run position. Do these tests when the coach does not start. Let me know what you find.

Pete Bustabad:
03/28/2017, 12:12:48 PM
Reply

Do you have anything like the stabil-air suspension kits for w-22??

Alan Sanders:
03/30/2017, 09:13:43 AM

Steve, We do not have anything that is like the Stabil-Air kit that Workhorse previously had available. The suspension kits we offer do not use air bags, you can see those kits here http://www.brazelsrv.com/Package-Deals/Suspension-Packages/Workhorse-W20-22-24-Suspension-Packages .

Keith Conley:
05/04/2017, 08:18:01 AM
Reply

Hello, I have a 2008 Winnebago Destination 39W, on a 2007 UFO Chassis. Of course it's a 8.1 with a Allison 6 spd. I want to know, what the torque value is for the Koni 99B-3209 front shocks, upper and lower. I need to know what that value is for tighten. Also, I need to know the Torque value for the rear's as well. I have the 8805-1002. Any help would be appreciated. I look forward to seeing you guy's on the trail, as I have some upgrades I may need. You have come very, very recommended. Thanks

Alan Sanders:
05/17/2017, 11:01:14 AM

Keith, Sorry for the delay in response. The torque for all the 3/4" grade 8 bolts are 420 lb ft with dry threads, and 320 if the threads have anti-seize or other lubrication on the threads.

Norman Gunderson:
06/19/2017, 05:42:41 AM
Reply

I have a 2008 Workhorse 8.1 that seems to have the wrong ppm programed in the ECM. The speedometer reads right about 10% faster than it should compared to my GPS. The milage is out also. Can you reset the ppm to correct this? I still have the stock tire size, so I think it has been this way since new. I just bought it a year ago and would like to get it to read the correct speed and distance. Thanks for any info.

Alan Sanders:
06/19/2017, 07:14:52 AM

Norman, Could you email me your VIN so I can see what you have? Once we have that, we can discuss what is going on. Please email the VIN using the contact form. Looking forward to helping out.

Mike@ Sals autoER:
06/29/2017, 09:30:47 AM
Reply

I am working on a 2002 Workhorse W22, 8.1. The owners were heading home to Wisconson in this rig they had purchased at a small "Mom and Pop" car lot in Ocala, Florida. They made it to our sister shop in Gainesville, Florida, and the rig went into " reduced power" mode, with no throttle response. The tech there cleaned the T-body, and it seemed good, until they got back on the interstate, where they limped it to our shop. I scanned for codes, and got the dreaded P1518. It was late on a Friday, and I really have no info on that chassis, so they were going to try a local RV dealer, but got little response. They flew back to Wisconson, and left the rig with us. Without a wiring diagram its tough to diag, so did the next best thing...throw parts at it. Replace the throttle pedal, no change, tried a new t-body, nope, then the TAC module itself. Nothing seems to help, but we can return the pedal and t-body. I am trying to check the Data lines from the TAC to the PCM, but cannot verify which ones at the PCM are the proper wires. I have been attempting to use a diagram from the same year 3500 Van with the 8.1, but am struggling with which "orange/Black, cir. 1061" and Dark Blue/White cir. 774" is at the PCM. The PCM is getting no info from the module, but cannot determine if the module isn't sending, or if the PCM isn't recognizing and processing it. There is very limited throttle response, maybe from 800 RPM to 1600 RPM, with the throttle wide open. The rig is a 2002 and only has 4750 mikes on it. I have looked for evidence of rodents, but found none. Any help/direction would be appreciated. We are getting no help from the RV dealers in the area. Thank you! Mike

Alan Sanders:
06/29/2017, 11:56:13 AM

Mike, I have sent some information to your email.

James Addison:
06/17/2018, 02:25:56 PM

If like to get a hold of the wiring diagram also... Having same issue same motor.

Alan:
06/18/2018, 08:00:35 AM

James, I have sent the diagnostic information for that code to your email.

chris dyess:
08/10/2018, 08:59:08 AM

I am having the same problem. I have a 2005 Fleetwood Motorhome and the 8.1. I slowed to turn and the engine light came on and reducing power warning light. was runnung good up to this point. Any help would be appreciated Chris

Alan:
08/13/2018, 05:19:44 PM

Chris, If you have had no other symptoms other than this one and the issue has cleared and not come back then I would not worry. However if this is still a current issue, then I would say that there are many things that can cause that problem but most common is the TAC module itself. You will need to scan your engine for codes and send me the code you are getting and I can send you some diagnostics for it.

Crosby Kennett:
08/07/2017, 07:27:27 PM
Reply

Hi Alan, I have a new to me workhorse chassis with a Fleetwood Terra on it. I replaced the headlight switch and started having problems with the headlights. After headlights turned on for about 30 or 40 seconds the headlights cut out (both) and flicker and don't operate. I took it to a reputable truck shop and they said the DRL module was NG so replaced the whole dash wiring harness. $$$ and still have the problem. They said the switch tested okay. With headlight switch in intermediate position DRL provide reduced power to headlights with no problems. Turn on the headlights and you're okay for a very short while until they all kick out. Any advice would be appreciated. Thank you. Crosby

Alan:
08/08/2017, 12:08:14 PM

Crosby, Could you give me a call so we can discuss? There are some Q&A's that we need to go over. 360-736-9494

Steven Johnson:
08/31/2017, 05:58:38 PM
Reply

2008 Winnebago Destination on a UFO chassis. Having problems with the auto brake release. When the yellow button on the dash is pushed to release the brake you can physically feel the brake release but the dash displays "parking brake on" with a red ! flashing. When this occurs my brake lights illuminate and stay on all the time. No one seem to know how to fix this problem. Coach has been in the shop for two weeks, need help.

Alan:
09/18/2017, 07:25:49 AM

Steve, Please contact us VIA phone to discuss the issue. 877-786-1576 Ask for Alan.

Ken Horn:
11/16/2017, 09:10:14 AM
Reply

I have a 2005 Workhorse P32 with the J72 brake system. It is a Winnebago Sightseer. We were in a campground for about 2 weeks when I started the engine. The brake pump started to run immediately. I did a brief experiment to determine that the RV is moveable but, sine I didn't have to go anywhereI. shut it down. There was no indication of a problem prior to us parking. Any thoughts?

Alan:
11/16/2017, 09:14:59 AM

Ken, Sounds like the parking brake module or the parking brake pump relay are having an issue. I would unplug the controller and start the engine to see if the pump still runs. If it does then you need a pump relay, if it does not then the controller is the issue. Either way I would recommend the US2078 kit that will replace the controller, and install a line lock. This is so the brake will not apply while you are driving the coach, and burn up the 3K$ brake on the back of the transmission. We have the kits in stock with free shipping.

Ken horn:
11/20/2017, 11:53:11 AM

Replaced the pump relay. No difference. Read the install instructions for the kit. Mine is a P32 chassis and the mounting instructions are for a 24 chassis. Not clear----does the kit replace the proportional solenoid? If not, would failure of that solenoid cause the motor to run?

Ken horn:
11/20/2017, 11:58:43 AM

In addition, why does the blue hydraulic line need to be disconnected at both ends? Can't it be disconnected from the block and then connected to the new unit?

Ken horn:
11/20/2017, 11:58:45 AM

In addition, why does the blue hydraulic line need to be disconnected at both ends? Can't it be disconnected from the block and then connected to the new unit?

Alan:
11/20/2017, 12:58:41 PM

Ken, You are correct, there are no instructions for mounting the controller on a 2005 P32 chassis. However it comes with two self drilling screws and can mount where ever the wires reach. All the rest of the installation instructions are the same. As far as the blue hydraulic hose, that depends on how the mounting arrangement ends up for the Ultra Save valve itself, sometimes it is better to turn the hose around due to one end having a 90 degree and the other end being straight.

Ken horn:
11/20/2017, 01:30:33 PM

OK. What about my question about the proportional valve?

Alan:
11/20/2017, 02:57:19 PM

Ken, Our kit does not replace that valve. You are correct, if you are having an issue with that valve that could make the pump run on and not build pressure, but the pump would not run with just ignition on and not in drive if the controller was operating correctly, and that valve gets it's 12 volts from the controller.

Ken Horn:
11/21/2017, 07:41:40 AM

So then, ,the us2078 kit should solve my problem? I noticed that the instructions said nothing about bleeding the system. How is that done?

Alan:
11/21/2017, 07:56:21 AM

Ken, Yes, the US2078 should cure the issue you are having. The system is self bleeding, just cycle the pump a few times.

Ken Horn:
11/29/2017, 09:47:05 AM

I have installed the kit and everything seems to be working just fine. It was quite a challenge to mount the parts on this P32 chassis. Ended up using stainless steel pipe clamps to hold the valve in place. For everyday driving maximum safety, should the valve be in the bypass or non-bypass mode? Thanks for all your help.

Alan:
11/29/2017, 12:45:20 PM

Ken, Glad to hear that you are operational again! You would want the red knob pressed in and turned clockwise.

Gary Croson:
02/28/2018, 04:53:33 PM
Reply

Hello Alan, I purchased a 2003 Winnebago Adventurer 35U workhorse chassis 8.1. I drove it 2hr after pickup and it ran fine plenty of power. I stopped and filled the tank and it started running rough and would not do over 10-15 miles an hr. I stopped on the side of the road for about 5-10minutes with the motor off and it restarted just fine and no miss and plenty of power. The next several days started right up in the driveway and we went to have the propane tank filled and were on the road for about an hour cut the motor off and it took about 20 minutes to fill the tank. I started the motor and it ran very rough and could not go more than 10-15 miles an hour. I stopped on the side of the road for about 10 minutes with the motor off and it started right back up and ran like nothing happened plenty of power no miss. I have a code reader and the codes were P1516 and P0151 . Before I go and start throwing a lot of parts at it what would you suggest. I have checked at the throttle body and the Tac for broken wires by pulling each wire and doing the wiggle test while it is running but no luck in having it fail vin # 5B4MP67G733364685 The motor home has 18530 miles and I have all the inspection papers and work done. I notice the spark plug wires were changed twice at 14000 and 15000 mile because of cyl 5 and 6 wires were bad. Any help would be greatly appreciated

Alan:
03/02/2018, 11:06:18 AM

Gary, I have sent you some diagnostic information via your email for the P1516 code. This will be the issue if you had a "Reduced Engine Power" displayed on the dash. Usually it will come back to the TAC Module itself, but it could be several other things also :-) Take a look through the diagnostic I have sent and see if that helps to narrow it down. I would have posted that information here, but it does not copy and paste well for the format of it.

John Olszewski:
03/16/2018, 09:30:31 AM
Reply

I have a 2005 Winnebago ( VIN 5B4MP67G453403770 ) on a Workhorse chassis. A 5 speed Allison transmission. The connector came off of the OD switch. The cable labeled OD SW has two connectors on it. Would you know which connector goes on the OD switch? Switch has 6 lugs. One connector has a black and gray wire. The other connector has a black,purple,orange, and gray wire. Thank you very much. You have my Actia instrument cluster doing the 105297R repair.

Alan:
03/16/2018, 11:13:44 AM, www.brazelsrv.com
Reply

John, I have sent you the wiring diagram for your overdrive switch to your email. Please let me know if you have any further questions :-)

John Olszewski:
03/21/2018, 04:13:43 PM

Sorry,but I did not receive any wiring diagram yet. Thank you,John

John Olszewski:
03/22/2018, 10:39:28 AM

Could you please email me the wiring diagram again. Thank you,John.

Steve Sensenig:
03/24/2018, 05:24:01 PM
Reply

2005 Damon Intruder on a Workhorse chassis with the Chevy 8-cyl engine. A couple months ago (we've been relatively stationary since, trying to solve this problem so we can continue traveling), pulled up to a stop sign after an uneventful 2-hour drive, and the engine stalled. After that, it would stall at idle, and I would have to give it gas to stay running, then "two foot" (one on the brake, one revving the engine) to put it in gear and pull away. It would run ok once I got up to speed, but acceleration was pitiful and it still felt a little rough. And as soon as I came to a stop, if I didn't "two foot" it again, it would stall. So far, we have replaced all the plugs and wires at one mechanic, had another convince me it was a bad tank of gas, so changed the fuel filter and put fresh gas and additive in, but the problems still remain. The first mechanic thinks it might be related to the EMC as they unplugged a couple of sensors and said the computer didn't throw any codes. Any other thoughts? And if it is possibly the EMC, how does one get it tested and/or replaced? I can't find information online about it, and the mechanic claims he called around with a part number Workhorse gave him and couldn't find a replacement computer anywhere. :( Not exactly what I'm wanting to hear, ya know? ;) Anyway, any advice you might have would help tremendously. steve :)

Steve Sensenig:
03/24/2018, 05:29:25 PM

Sorry.....ECM, not EMC ;)

Alan:
03/26/2018, 07:36:12 AM, www.brazelsrv.com
Reply

Steve, I would check the injector and coil harnesses. If there are no codes, it is probably the power supply to one of the banks on the engine. The computer sends grounds to the coils and injectors to fire them, there are two fuses the supply the left and right bank constant power to each of the coils and injectors. I would bet there is an issue with one or both of the power supplies to those harnesses. I have seen many things that caused issues similar to this, one was the A/C compressor pulley rubbing on the harness, and also some failed splices, plus stretched wires. Try moving the harnesses on the top of the engine on both sides with the engine running to see if you can make it run better with the movement of them.

Dean Schmidt:
04/16/2018, 02:13:31 PM
Reply

2004 Workhorse Chassis p32 under a fleetwood tiera. Cruise control is not working as it should. When pressing the "SET" function at speed I get a momentary (slight rpm) boost as I might if I were setting the cruise. However a release of the SET switch the vehicle goes back to manual speed. Continuous pressing the the SET switch does a this momentary rpm adjustment but I cant get the Cruise to go into SET Mode. All fuses have been checked and the brake switch has been checked as well. So wondering if this issue is in the TAC module or other? thanks in advance. Dean

Chuck Shrode:
04/26/2018, 03:29:48 PM
Reply

I purchased a (Harbor Freight) "Zuric ZR8" OBD2 Code reader, specifically for use with the Workhorse Chassis, W22. After making the connections, the code reader indicated that there was compatibility issues with that vehicle. I do not understand if the problem is the "reader or the vehicle. I did try to update the software and spoke with a representative, who claimed the reader was new and that no updates were available. Question: is the subject vehicle compatible with OBD2, other than just for smog testing?

Gary Croson:
05/31/2018, 05:51:22 AM
Reply

Hi Alan ,would you have vacumm routing for a 2003 winnebago adventurer 35u w22 . The dash a/c stops blowing when climbing a steep hill.It will come back on after grade. Thanks Gary

Alan:
05/31/2018, 07:35:23 AM, www.brazelsrv.com
Reply

Gary, There really is no vacuum diagram, but usually the vacuum is taken off the back of the intake manifold and ran directly up to a vacuum ball under the hood. This is done by the body builder. Now also, the A/C compressor clutch is set to be disabled by engine load and throttle position. That is done that way to provide as much of the engines power as possible to the wheels when you are demanding it.

Gary Croson:
06/02/2018, 04:07:55 AM

Thanks for getting back.

Linda H:
06/19/2018, 03:01:48 PM
Reply

I have a 2003 Winnebago Adventurer 33V on a workhorse chassis. I need new and hopefully brighter headlights. Any suggestions as to where to obtain?

Alan:
06/19/2018, 04:17:36 PM, www.brazelsrv.com
Reply

Linda, Normally headlights are not something that we get into, due to them being a body builder part. However I do know that some coaches are not getting enough amperage to the headlights through the factory wiring. So I would suggest starting with checking to see what voltage you have at the headlights when the engine is running and the lights on. You should have at least 13.5 volts (or close to it) at the headlight connector. If you do not, then I would suggest wiring in a relay to each headlight so that you get proper battery voltage to them, making them as bright as they can be. Connecting the relay... - Cut the power wire to the low beams about 6 inches from the connector on the headlight - Install that cut wire onto pin 86 of the relay - Ground pin 85 - Connect pin 30 to a 30 amp fuse or breaker - From the breaker or fuse straight to the battery - Last connecting pin 87 to the cut wire left on your headlight connector

Peter LaPointe:
01/03/2019, 06:33:34 AM

Hello Alan, this is very helpful to me and I will make this mod but I think I have a deeper problem. Yesterday while driving my headlights dimmed to nothing. Dash lights died as did rear view camera monitor and 12v power sources (cigarette lighter). My AC quit working and my levellers suddenly deployed without any input! My AFT running lights are getting 12v while my headlights and forward running lights are getting 6v and 4v respectively. I've tested all the relays I can find (all test good). I've checked grounds, alternator and belt, all good. Chassis battery is holding 13v. I'm basically dead in a Lowe's parking lot and need to get home (300miles to go)

David A. Griffin:
07/05/2018, 01:51:12 PM
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Hi, Alan. I have been trying to reach you by phone (had left three messages on voice mail) to follow up on my telecon with you about my autopark issue on my 97 Fleetwood Storm (I had given you the last eight if the VIN). Would you prefer to call me back at 719-687-0911 so I can report on what I found out after your suggestions, or do you want me to email you the findings? Look forward to hearing back from you one way or the other. Thanks.

David Griffin:
07/10/2018, 01:33:26 PM
Reply

Sorry I missed your call today. I left you a voicemail. When you get a chance please call me at 719-687-0911.

DAVID GRIFFIN:
07/11/2018, 11:14:09 AM

Alan: I just sent some info as follow up through your CHAT LINE about what we discussed concerning the LIGHT SWITCH.

Roger Heikes:
07/14/2018, 09:29:30 AM
Reply

Hello Alan, 2003 Winnebago Adventure 35U on Workhorse W-22. Have lost operation of drivers side low beam. All other lights work and function. When switching between low and high the drivers side acted like the element was going until if finally failed. A check of the bulb found it to be good. Replaced headlight fixture as I found one mounting tab missing. Also, I had just replaced headlight switch along with dimmer switch. Have since reinstalled original headlight switch. Same problem continues. Any suggestions would be appreciated before I did into this. Do the low and high beams operate thru some kind of relay?

Alan:
07/18/2018, 04:11:41 PM, www.brazelsrv.com
Reply

Roger, I have sent you some wiring diagrams for the headlight circuits. From the looks of it, if you lost only one side of either high or low beam then it would be in the wiring if it is not the bulb. This is because the lights share the same circuit side to side.

Roger Heikes:
07/18/2018, 10:29:39 PM

Thank you for the wiring diagrams. I intend to study them as I believe this problem is not yet over. I was all set up this morning to run a wire from one side to the other just to make the left side work if powering the circuit backwards to locate the problem area did not work out. Upon turning on the lights to verify that I was on low beam that left light came on. Thanks again.

Brad Fyfe:
07/19/2018, 11:04:17 AM
Reply

Hi, I have a 2001 Winnebago brave with the 8.1 gm engine. It has a problem that no one has been able to fix. It runs great for the first 30 minutes. After that, it tends to pop under a load such as climbing hills while towing a trailer, or just climbing a long hill. Mechanics have replaced the crank sensor, fuel filter, plugs, wires, oil, fuel pressure regulator, 02 sensors, and air filter. We even dropped the tank and redirected the return fuel away from the fuel pump pickup and drilled extra holes in the bottom of the plastic bowl that the pump sits in just to make sure that it gets fuel. Nothing fixes it. We put a fuel pressure gauge on it and ran it up Pack Monadnock Mountain to see if the pressure would drop off, but it didn't. My thought is that something starts failing when it gets very hot. I will not see any issues until it has run for a good half hour, then the popping starts under load. It will run fine at about 1/2 throttle so I usually back off of the gas to stop it. It only has 18,000 miles on it. Do you have Any ideas???

Alan:
07/19/2018, 11:39:34 AM, www.brazelsrv.com
Reply

Brad, I would suggest our data recorder part# UPREC not to sell you something, but I think at this point it would be the smart choice before I guess like everyone else has. What will happen once you order this part, we will have you plug it in to your OBD2 port and drive the coach until you are able to repeat the issue. You would email the data file for us to review after you capture the failure on the recording. We will review the data file and give educated advice on what to check to pin down the issue.

Brad Fyfe:
07/22/2018, 09:15:32 AM

Hi, I called in to you guys but got a different guy who seemed very knowledgeable. he said to check the wires. I explained that I replaced them with Taylor 409 extreme service rv wires for my 8.1 chevy (2001 Winnebago brave 31 on p32 chassis). I went to check them today, and sure enough, the rear left Taylor wire was burned right through its boot and insulation. I ordered a set of Access ceramic boot wires to try out, and I'm going to get the Taylor wires because they are under warrantee. I'll have them as spares. I hear that there is a cooling kit from Workhorse because of this issue, so I'll look into this as well.

Larry Dufour:
08/28/2018, 07:04:17 PM
Reply

Hello: I just recently purchased a 2004 Motor home with the 8.1 workhorse chassis. When I pulled into the garage for the inspection sticker a machanic said it smelled like it is running very rich. He thought it might be the fuel pressure sensor. I am only getting 6.6 mpg. Should I replace the sensor? Thank you for your time

Alan Sanders:
09/06/2018, 08:15:15 AM, www.brazelsrv.com
Reply

There is not a fuel pressure sensor on that engine. I would get a scanner that you can monitor fuel trims on and see what they are showing for the fuel mixture adjustment. You can use something like the scan gauge 2 and program the LF1 and LF2 to see the long term fuel trims. Anything showing more than an adjustment of 10% in either direction + or - is more than what GM calls normal. Once you have that information let me know and we can start to figure out what is wrong.

Mike Lazaro:
09/20/2018, 04:06:11 AM
Reply

Hi, I have a 2008 Winnebago Adventurer on a UFO chassis. Having problems with the auto brake release. When the yellow button on the dash is pushed to release the parking brake, it releases with no problem, however, my brake lights illuminate and stay on all the time. The cruise control and grade brake don't work and when the ignition switch is shut off the HCU cycles on and off to maintain pressure. Any help would be great appreciated..thank you

Alan Sanders:
09/20/2018, 10:27:19 AM

Mike, As far as the first parts of your complaint, you most likely have an issue with the brake light switch. That is located on the master cylinder, they call it a master cylinder travel switch, make sure that it is installed completely. For the last part, not sure why the brake pressure motors would be running with the key off. They should only operate with the ignition on. Here is what it states in the service manual for the HCU after replacing the entire unit..."Reinstall the 30-amp motor fuses and turn the ignition ON. Both motors will start running until both circuits reach the cut-off pressure at approximately 2000 psi (138 bar)." So that tells me that the key should be on before the motors are allowed to build pressure in the accumulators. It really would not make sense for them to be allowed to operate with the key off, because the motors would run the battery dead. It sounds like you either have a wiring issue or an internal issue with the HCU. More often than not, the HCU has to be replaced. I will send over a diagram of you plug on the HCU so you can make sure that you are not getting 12volts at the ignition circuits when the key is off.

Mike Lazaro:
09/30/2018, 09:25:20 AM

Hi Alan, Thank you for getting back. Some feed back on how I made out.. I located the brake switch on the master cylinder as you indicated. Upon removing the plug from the switch the brake lights went off proving the switch defective. The interesting part is the HCU no longer cycles with the ignition switch off. Plugging the connector back in, brake lights went on and HCU started cycling again, with the ignition in the off position. Ordered up a new brake switch and installed and all is working properly again. Thanks again for your help.

Bob Ashton:
09/20/2018, 09:55:54 AM
Reply

We also have a 2008 Winnnebago Adventurer Limited on a Workhorse UFO chassis with what appears to be the same problem as Mike Lazaro. The auto brake release works when the yellow button is pushed in however, the brake lights illuminate and just stay on permanently. Not sure whether the cruise control works or not as it is something we don’t normally use but the grade brake doesn’t work and when the ignition is shut off and we are level, the HCU is cycling on and off on fairly regular 10 minute intervals. This problem was evident before the HCU was replaced in June because of all the warning lights and alarms indicating a failing HCU. Replacing the HCU solved the warning/alarms problem but had no effect on the brake light, grade brake, frequent cycling HCU events. Our turn signals work, but the 4 ways only flash in the front but not the back. Any help would be much appreciated.

Alan Sanders:
09/20/2018, 10:37:10 AM

Bob, If you have checked your brake light switch and that checks "Okay" then you will need the Wabco "Toolbox" toolbox software to do further testing to see if the brake light signal is being switched properly by the HCU module. This would apply to Mike Lazaro as well if the brake light switch is working properly. As far as the HCU motors cycling, that is normal and should be expected when the ignition is "ON".

Bob Ashton:
09/20/2018, 01:40:09 PM
Reply

Al, where is the brake light switch?

Alan Sanders:
09/20/2018, 04:34:32 PM

Bob, it is located on the master cylinder. The Workhorse part # is W8002767 you can find that on www.urvp.com there is a line drawing of it. Looks like at the moment there is 1 available if you need it.

Rick Sieminski:
09/29/2018, 02:05:27 AM
Reply

I get the dreaded "Reduced Power" message, and codes P0120, and P2135. I have: replaced the Throttle Body(TB)/TPS replaced the TAC *still get the error checked the continuity from the gas pedal to the C2 on the tac checked the continuity from the throttle body connector to the TAC, and from the TB end they are all fine, but there's more pins on the TAC C1, than on the TB I have traced 3, if I remember correctly, to the ECM/TCM (4, 5, & 14) 2 seem to be grounded (6 & 15) the documentation that I have says 15 is ground, BUT 6 is supposed to be "CHMSL SUPPLY VOLTAGE"? Could this be the problem? and 3 I can't seem to find out where they go (7, 12, & 13) the documentation that I have says 7 is "IGNITION VOLTAGE", 12 & 13 are "UART SERIAL DATA"? BUT I can't seem to trace them Any ideas? Thanks, --Rick

Alan Sanders:
10/04/2018, 08:44:05 AM

Rick, What is the last 8 digits of your VIN?

joie:
10/14/2018, 02:38:59 PM
Reply

2005 winnebago adventurer workhorse w22 dash says "No J1050 Activity". Had this show a couple months ago when we got in to leave on a trip and was a blown fuse outside but checked all inside and outside fuses and all are good and have 12v. Coach was running fine till some idiot in a CRV cut us off so she had to get on the brakes pretty hard and when she did the engined died and now gives this error trying to restart. Any ideas?

Alan:
10/17/2018, 12:38:02 PM

When the dash shows no J1850 activity that means the cluster cannot communicate with the PCM. Does the engine crank?

joie:
10/19/2018, 03:10:19 PM
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Engine doesnt even attempt to crank. Unplugged replugged cluster still no luck checked all fuses no luck looked for loose wires no luck and OBD2 scanner gets no response from ECU.

Alan Sanders:
10/24/2018, 07:24:48 AM

Joie, I would double check the ECM/TCM fuses under the hood...This sounds like a failed TCM. It has an internal issue and pops the fuse for the ECM and the TCM due to them both being on the same circuit for the power supply. If you do find a blown fuse for them, unplug the TCM and reinstall the fuse and see if it pops again, if it does not then plug it back in and see if it pops then. If it does after it is reconnected then you will need part# 29537441 from the www.urvp.com site.

Mac kinsella:
10/23/2018, 10:28:43 AM
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I have a 2006 Safari Simba on a Workhorse Chassis 8.1ltr Alison Trans.after having the RV parked for a while I went to start it and all the gauges went haywire, rpm went about 11/2 in below its norm same with the speedometer and the gas gauge went as far to the right as is possible any help would be appreciated. incidentally where are the chassis ground points on this RV Thank you Mac Kinsella

Alan Sanders:
10/24/2018, 07:29:04 AM, www.brazelsrv.com
Reply

Mac, You should remove the cluster and send it in to us with your information inside the box so that we can check it on the bench to see what is going on with it. You probably just need to have the gauge motors replaced. We do not charge any thing to check if for you, you would just need to pay shipping. If there is something wrong with it we will call you and you can choose to have us repair it or not. Most of the grounds meet at the back of the head on the drivers side of the engine.

Mac kinsella:
10/27/2018, 09:09:56 AM

Thank you Alan, I have the cluster out right now and the motors are visible, I am leaving for Texas next week for the winter and that would be the best time too send it out, if it is the motors do you have any idea what the cost of replacement would be/ Thanks again Mac Kinsella

Peggy:
10/30/2018, 04:15:05 PM
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Hi, I have a 2004 Damon Daybreak P32 Workhorse 8.1, recently had both front ABS sensors replaced, drove it home about 2 weeks later went out put gas in it, drove it about 20 miles no problems. Couple of days later replaced a part In the electric Steps, turn on RV to see if steps worked and engine light came on and reduced engine power displayed in lcd. Drained and replaced coolant after reading several post. Reduced engine power went off but engine light is still on. Any help or info you can give me would be great! Thank you in advance for your reply!

Alan Sanders:
10/31/2018, 07:41:41 AM

Peggy, The reduced engine power is only activated by the throttle system. Here is what the engine controls manual states about "Reduced Engine Power Mode" REDUCED ENGINE POWER MODE When the PCM detects a condition with the TAC system, the PCM may enter a reduced engine power mode. Reduced engine power may cause one or more of the following conditions: • Acceleration limiting – The control module will continue to use the accelerator pedal for throttle control; however, the vehicle acceleration is limited. • Limited throttle mode – The control module will continue to use the accelerator pedal for throttle control; however, the maximum throttle opening is limited. • Throttle default mode – The control module will turn off the throttle actuator motor and the throttle will return to the spring loaded default position. • Forced idle mode – The control module will perform the following actions: – Limit engine speed to idle by positioning throttle position, or by controlling fuel and spark if throttle is turned off. – Ignore accelerator pedal input. • Engine shutdown mode – The control module will disable fuel and de-energize the throttle actuator. You will need to scan the engine computer for the code that is stored, then I can send you the diagnostic information for that code.

chad g clayton:
12/19/2018, 06:22:19 AM
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I have a 2006 Magellan RV 35', workhorse chassis. The periodic problem sends a lean code which shows oxygen sensor, left bank. I know this is just a symptom. It runs fine, generally until I am in warmer weather going up a long incline, then it loses power and shifts out of overdrive. It seems like it is going into limp mode. When I pull over and stop and then try to accelerate, it has very little power, then it will backfire and gain power, after I take off and drive for 3 or 4 minutes. During those 3 or 4 minutes it usually won't get above about 10 mph. If I clear the codes and let it sit for 5 minutes it usually takes off like nothing is wrong and may not have the same issue for 50 miles or 500 miles. When it is having the problem at a stop I can press the accelerator pedal and the RPMs usually won't go above about 3,000. It seems like it always runs rich on the left bank, as the tailpipe is blacker than the right side. The mileage is never above 7 mpg.

Alan Sanders:
12/19/2018, 12:33:56 PM

Chad, I would recommend getting a scangauge2 this will help determine the fuel ratio and how much it may be off. You will need to set it up to read the long term fuel trims. It almost sounds like you are having a fuel pump issue. If you scan the engine and you see the fuel trims going anywhere near 25% on either side that is not good. You can also get a data recorder from us and then we can take a look for you. You just plug it into the diagnostic port and drive, once it fails then plug the recorder into your laptop and email us the file for review. You can purchase one from our site the part# is UPREC. Without some further information from your engine it is hard to say what is happening.

chad g clayton:
12/19/2018, 05:39:44 PM

Thanks, Ala. I actually borrowed a scanner that gives live feed and at 2500 rpms the long term fuel trims were at around 17.4%. I am not going to be taking the RV out for another 3 or 4 months and it probably won't act up until I get to Eastern Washington. If you still think the data recorder is a good idea, I can get one and plug it in for the next time I go on a longer trip.

Andy Theaker:
12/19/2018, 10:21:29 AM, www.monstermoovers.com
Reply

I am having a problem with a 2005 Fleetwood Southwind on a workhorse 8.1. It was driven to it's current location a couple of months ago. Come to move it now and it won't start, the jacks won't come up and the dashboard throws out a long beep followed by 21 short beeps. To throw a little more light on the subject, when the ignition is first turned on, the jacks light comes on and they will move for a second or so, then the beeping starts and the power is lost. Also, the lpg / gas changeover is lit, then goes out as the beeping starts. The engine spins over quickly but won't fire. I suspect some circuit / sensor cutting the power to the jacks and fuel and probably other places (ecu?) preventing it from firing but it's got me baffled. I also suspect the beeping it trying to tell me something but I have no idea what! It hasn't thrown any codes, pending or otherwise. There is, apparently, an immobiliser / alarm on the vehicle but the owners have never used it and have lost the fob. I suspect the problem lies here, somewhere but not sure where to start as I can't find any information. I don't even know if this was a Fleetwood add on or a standard workhorse fitment. Thanks in advance for any clues you may be able to give me Andy

Alan Sanders:
12/19/2018, 12:36:39 PM

Andy, the security device is not from Workhorse. However, if you could provide your VIN I may be able to give you some direction that will if nothing else eliminate some things.

Andy Theaker:
01/26/2019, 07:28:28 AM

Hi Alan, thanks for the response, I didn't realise you had responded, apologies. I Checked the coils and injectors today. No power at either but the fuse that supplies them is live. I may however have not checked the injectors correctly as they all have a black wire and them another of various color from red, orange, yellow and I checked for power on the colored one... There is still this pronounce relay click a second or two after the ignition goes on, then most things go dead (the fuses for the injectors and coils are still live. I found two immobiliser 'keys' (the plug in types from Laserline) but can't find anywhere they go.. I don't even know if they are relevant to this vehicle but hard to see that they could be from another vehicle because if this was the case, that wouldn't be running lol. I can smell petrol so am guessing fuel is getting there. I don't know if I need to go back and recheck the injectors on the black wire. I considered running a 'hot' directly to a couple of the coils to see if they would fire but in light of the injectors, I thought I would ask first. A strange thing though, at one point - a couple of times - it did sound like it fired very briefly. Whether it's optimistic imagination or not, I'm not sure. The VIN number is 5B4MP67G053402714 Thanks so much for your help. Andy

Alan Sanders:
01/28/2019, 02:38:43 PM

Andy, Do not run power to the coils. The coils are fired by a ground from the computer and have a constant hot from the fuse to them. The very first thing to do is get a code scanner and see what codes you have stored in the computer. Let me know what you find.

Andy Theaker:
01/29/2019, 01:57:10 AM

Hi Alan, I scanned it initially and it had thrown any codes, pending or otherwise. I'll do it again and come back to you.

Andy Theaker:
01/30/2019, 08:30:26 AM

I have run a full scan and there are no codes, current or historical, which amazes me. The ECU appears to be communicating fine with the scanner

Ssonny Truitt:
12/28/2018, 09:39:50 AM
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I have a 2003 Monaco Safari Trek with the 8.1 vortec engine. Recently programmed the Scan Gage to read fuel trims and they were high....25 at idle and approx 15 cruising. Cleaned the MAS, verifid clean air filter an ran fuel injector cleaner for two tanks. Now reads 18 at idle and 2-8 cruising. I think this indicates a vacuum leak but am having trouble finding a place to check. A vacuum line diagram would help. Also, right bank is always about 2% higher than left bank. Any ideas? Thanks. PS I'm running Brazel's switches on the APB and have no worries.

Jon Brazel:
01/03/2019, 04:13:14 PM

Hi Sonny, High fuel trims at idle that reduce under load are almost always a vacuum leak. I don't have a diagram but the most common spot I see leaks is at the back of the intake manifold there is an unused port that should have a rubber cap. Sometimes this cap develops a crack or is completely missing. I am not worried about the 2% split on the banks, if it was 5 or more then I would begin some investigation. 2-8% under load is perfectly fine, specification from GM is +/- 10%.

Joie:
01/09/2019, 03:25:14 PM
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Do you guys have a pinout for the ECM? I cannot find one so I have no way to test if power is getting to the ECU. 2005 Winnebago Adventurer 37B on a W-22 chassis.

Alan Sanders:
01/09/2019, 05:40:07 PM

Joie, I sent you an email with the information that you would need.

Richard E Vie:
01/10/2019, 11:30:51 AM
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Thanks for all the help with my workhorse w22 holiday rambler MH. The second tcm controller worked perfect so far. Finished our trip to Florida with better gas mileage and better driveability than ever. But after driving short distance w tcm removed to get to repair center in Mississippi a ck eng (little eng block on right side of instrument panel) lit up. After putting in new tcm light stayed lit. Nothing wrong showing on any gauges and nothing showing up on the scan gauge. Engine runs perfect. Any ideas?

Alan:
01/10/2019, 11:32:57 AM

I would go and have the codes cleared and see if they come back. I am sure it is because it was driven with the TCM disconnected.

Jeffrey Cox:
01/31/2019, 06:13:05 AM
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I have a 2006 Allegro Bay Vin#5B4MPA7G553408432. W24 chassis.Having problems with the J72 park brake system. The pump was running constantly and not releasing. I found the park brake housing assembly was leaking internally.I replaced the housing and hose that goes to it. I cracked the line going into the housing and cycled the auto park(released the brake and put in gear). The pump runs constant and is not building pressure. How can I tell if the pump is no good or if the solenoid valve is not working or stuck? Is there any other things that I should be aware of in my testing? Thank you.

Alan Sanders:
02/07/2019, 10:07:44 AM

Jeffery, see this diagnostic article. I think that it would help you , this one is for if you have a US2078 kit installed, but it will still help you run down the issue. https://help.brazelsrv.com/hc/en-us/articles/360021860692-J72-with-US2078-kit-Pump-runs-continuously

Gary A Croson:
02/03/2019, 09:36:09 AM
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I have a 2003 winnebago adventurer 35u workhorse . I purchased this unit used and I seem to be missing a air dam that screws to the firewall over the radiator is this a part that should be on the motorhome for cooling? Thanks

Jon:
02/04/2019, 12:27:23 PM

Yes there was what they called an "Air Diversion Panel" that covered the opening around the top and sides of the cooling pack to help direct airflow through the coolers and radiator. Unfortunately this is no longer available from Workhorse but can be fabricated with a rubber material sourced locally. Here is a link to a picture of what was previously available: https://www.ultrarvproducts.com/W0005312-Baffle-Recirculating-Air-Side-(Air-Diversion-Panel)

Andy Holstad:
03/01/2019, 11:16:15 AM
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I have A 2003 workhorse W 20 chassis. I developed a electrical short circuit when The articulating steering column wore a hole through one wire in the wiring harness that runs from the ignition switch to the base of the steering column where there is a harness connection block. I would like to remove that harness from the steering column to repair the damaged wire. The termination block for the harness next to the ignition switch has some security type screws. What do they call the screwdriver that can remove those security screws, (they are like reverse torx head screws)?When I remove the block which is next to the ignition switch will I have any surprises like a spring popping out or parts dropping off? Thank you for your time and any possible suggestions.

Alan Sanders:
03/11/2019, 09:06:16 AM

Thank you for calling, let me know if you need further assistance!

Gerry Linneweh:
03/10/2019, 08:16:57 AM
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I have a 2005 Winnebago Horizon. Recently the running lights are flashing with key in the accessory or off position. It was intermittent but seems to be happening more and more. Any ideas?

Alan Sanders:
03/11/2019, 09:07:17 AM

Gerry, Could you send me the VIN for your coach to help@brazelsrv.com.

Rich Holley:
03/14/2019, 10:00:30 AM
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I have a 2007 Workhorse W24 Chassis VIN# 5B4MPA7G373427516 that is new to me. Purchased with 90k on the clock; however one owner with a long list of maintenance records. When purchased, I noticed a significant misfire when driving, and brought it into the Chevy dealer I work at. Right off we discovered a broken spark plug wire on #5, and changed all the plugs and wires. This solved my issue for the next few hundred miles, then last week on a drive from the storage yard to my home, she started to miss again and heard a couple of backfires. I downshifted and the miss went away. I decided to bring it in again to put a Tec-II on it and hook up the laptop to see what the issue was, and on the way in, I noticed she was hesitant and missing under acceleration, but only on the 2nd part of the trip after she warmed up (note- no lights or codes thrown). Here is what we found when we plugged in.... 1. An intermediate miss in cylinder #5 starting at 2500 rpms, and ceasing back down around 2000 rpms. 2. Only occurs on a hot engine. Sat overnight and this morning- no misses could be seen. 3. Replaced coil pack on #5 cylinder with no change when hot. 4. Confirmed spark plug and wires (replaced two weeks ago) were good. AC Delco plus and Napa Wires. My mechanic believes it is heat related, based on the clean cycle it ran this morning and possibly electronic related. I am sure that you have heard of similar issues... any thoughts or things to check while I have it here? Thanks for all you guys do. Rich Plant City, Fl

Alan Sanders:
03/14/2019, 10:34:18 AM

Rich, This is a very common issue. I would replace the plugs and wires with these part#s and you will not see the issue again. Spark Plug Wires SPW8100, Spark Plugs 41-101. We have these in stock and the wires are a solid stainless core lifetime replacement wire. If you are not showing a code and you have a misfire on #5 this is most always the issue. I would check for an exhaust leak around the manifold that may be leaking onto the wire contributing to the accelerated failure of the wire.

Rich:
03/14/2019, 02:22:25 PM

Thanks so much for the prompt reply, I will look up these parts.

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