Jump to content

Onan 8k quietdiesel error code 38


Recommended Posts

Genset will start and then immediately stop. Error code 38. Turn off all breakers on truck and still shuts down right after start (even before transfer switch kicks in). If flip breaker on the genset, starts and purrs good. Flip breaker in genset (all breakers off in truck panel) immediately shuts down. 

Wiring between genset and transfer switch? Transfer switch? (Transfer switch works fine on shore power as do all breakers). And help appreciated.  

Edited by lockmup68

2003 International Eagle 9200i, Cummins ISX, Freedomline

2007 Teton Scottsdale XT4

 

Link to comment
Share on other sites

The code 36 means it shut down without a shutdown command from the controller. The Onan sites seem to indicate that the most common causes of this are fuel related so it may be that when the engine is idling it gets enough but stops when a load is added. That could be a fuel filter or fuel pump, but those are just guesses based on what I read on other sources. 

Good travelin !...............Kirk

Full-time 11+ years...... Now seasonal travelers.
Kirk & Pam's Great RV Adventure

            images?q=tbn:ANd9GcQqFswi_bvvojaMvanTWAI

 

Link to comment
Share on other sites

He's reporting code 38. Overload. Sounds like a problem with the wiring between the generator breaker and the transfer switch. 

I have been wrong before, I'll probably be wrong again. 

2000 Kenworth T 2000 w/N-14 and 10 speed Gen1 Autoshift, deck built by Star Fabrication
2006 smart fourtwo cdi cabriolet
2007 32.5' Fleetwood Quantum


Please e-mail us here.

Link to comment
Share on other sites

9 hours ago, Darryl&Rita said:

He's reporting code 38

OOPS! 😡

A 38 is a general overload fault. Onan says this in the QD 7500 service manual:

Quote

Corrective Action:
1. Reduce the number of appliances running at the same time, especially those with high motor starting loads such as air conditioners. Start up with no load and let the genset run for five minutes to cool down the inverter.
2. If the appliance and air conditioner loading patterns have remained the same but genset performance has deteriorated:
A. Check for fuel and air leaks at each fitting in the fuel supply line. (Note: White smoke indicates air in the fuel.)
B. Conduct a fuel flow test and service as necessary (p. 14-1).
C. Remove the front and top housing panels (p. 6-4). Check for binding in the governor mechanism by pushing the actuator rotor clockwise by hand—against the action of the fuel rack return spring. It should rotate smoothly about 1/2 inch (12 mm) and return smoothly. If it binds or catches, remove the governor actuator base assembly and replace it or service the internal engine governor mechanism (p. 13-3) as necessary.
D. Readjust high-idle speed (p. 13-4).
E. Service the fuel injectors and injection pump as necessary (p. 12-1).
F. Service a worn engine (p. 12-1).

 

3

 

Edited by Kirk Wood

Good travelin !...............Kirk

Full-time 11+ years...... Now seasonal travelers.
Kirk & Pam's Great RV Adventure

            images?q=tbn:ANd9GcQqFswi_bvvojaMvanTWAI

 

Link to comment
Share on other sites

it is a diesel.

I checked all wiring between genset and transfer switch. Even with all breakers off, the generator shuts off immediately. If I turn the generator circuit breaker off, motor runs fine. According to the manual, if the breaker trips, the motor should continue to run. The breaker is not tripping, but shuts off the motor if it is on. Since there is no load at all on the generator (all breakers on truck are off, line from generator to transfer switch is less than 3 feet long and I inspected from start to finish. Transfer switch is working on shore power. So I'm going to try replacing the circuit breaker first. If that is not it, I'll start replacing wire. If wire does not fix it, then I guess it could be transfer switch, so that will be third option.

2003 International Eagle 9200i, Cummins ISX, Freedomline

2007 Teton Scottsdale XT4

 

Link to comment
Share on other sites

9 hours ago, lockmup68 said:

So I'm going to try replacing the circuit breaker first. If that is not it, I'll start replacing wire. If wire does not fix it, then I guess it could be transfer switch, so that will be third option.

It sounds like a problem in the Onan control circuit board, which is probably not inexpensive. I do not have access to a schematic of that board but I suspect that it receives some type of feedback from the output side of the generator's breaker and that output is triggering a false shutdown. Here's hoping that I am wrong!

Good travelin !...............Kirk

Full-time 11+ years...... Now seasonal travelers.
Kirk & Pam's Great RV Adventure

            images?q=tbn:ANd9GcQqFswi_bvvojaMvanTWAI

 

Link to comment
Share on other sites

 If you search Twinslan.net           

 

Lockmup, You may find your service document there.

 

 Kirk you may want to save this site.

 

 Now you also could contact.   (.           ). Really this name is outside floating around somewhere. When I find it I will post it.

 Safe Travels,   Vern

 

 

Edited by Wrknrvr
Link to comment
Share on other sites

The last Onan circuit control board I purchased was like over five hundred dollars and there were NO Dinosaur Electronics or other manufacturers or rebuilders or repair shops that would repair or replace them PERIOD and that was AFTER I tried all the external troubleshooting like breakers or switches or sensors or fuel related issues grrrrrrrrrrrrrrrrrrrrrrrr

HOPEFULLY Maybe the Onan troubleshooting procedures can get you by much cheaper.

I ran Onan's of all types and sizes for yearsssssssssss and could usually keep them going myself UNTIL I experienced circuit board problems on the later and new generation units. Give me the old two cylinder MUCH QUITER and smoother 1800 RPM units in the smaller 4 KW gas application.

Good luck let us know how it turns out

John T

 

Link to comment
Share on other sites

14 hours ago, Barbaraok said:

 You keep mentioning truck.  Is the generator tied into your truck, not just your trailer/5th wheel?

Yes, generator is mounted on the truck (HDT). I run the AC/microwave/fridge in the sleeper when we are running down the road. And it will run the trailer when we parking lot overnight. It can run a 50 amp trailer and a 30 amp trailer at the same time. This is a 2011 unit that only has ~700 hours on it. 

2003 International Eagle 9200i, Cummins ISX, Freedomline

2007 Teton Scottsdale XT4

 

Link to comment
Share on other sites

  • 4 weeks later...

Finally was able to get it into an Onan service center. We disconnected all connections outside of the genset. Same behavior, motor starts up and runs fine, flip breaker on, shuts down with NO load and no connection to anything outside genset. They are saying it is a ground fault, probably a wire rubbed through in the harness. However, they want to schedule me in late August to look at it further. I tried to open it up and see if I could find the short, unfortunately, in order to get the panels off, the genset needs to be dropped out of the truck as it sits too close to the airbags on the truck and not enough room to get the panel off, unless I am doing it wrong. It is only four bolts holding the genset cage, but that thing is heavy at 450lbs, so no way to do it myself. I'm calling around to onan service centers on our trip and trying to get an appointment somewhere in Canada. 

In the short term, borrowing a couple of Honda 2ks with a parallel kit to use for next two months and can return them on way back through. 

2003 International Eagle 9200i, Cummins ISX, Freedomline

2007 Teton Scottsdale XT4

 

Link to comment
Share on other sites

  • 1 year later...

I was getting code 38 as well.The generator would start run for a few seconds and shut down.I traced it to a broken ground wire just to the left of the main service access panel. There is a main ground post with many wires tied into it.I replaced the terminal and now it’s good as new.Hope this helps. I am an OTR trucker and relie on my generator.Had to due without until home time to properly diagnose the issue 

hope this helps others 

 

 

Link to comment
Share on other sites

  • 4 weeks later...

forgot to close the loop on this, the controller board failure. The bad part is the controller board is hard soldered into the inverter itself. Requires a replacement of the entire inverter side of the equation. It's a common problem and the bigger Onan/cummins service centers have them on the shelf. $2600 part, have to take the genset completely out of the rig to replace. runs like a top now. 

If I understood correctly, Onan redesigned and after 2018, they are now separate components and can be replaced separately. 

Shannon

2003 International Eagle 9200i, Cummins ISX, Freedomline

2007 Teton Scottsdale XT4

 

Link to comment
Share on other sites

  • 2 months later...
On 2/16/2020 at 8:49 PM, TonyGOTR said:

I traced it to a broken ground wire just to the left of the main service access panel. There is a main ground post with many wires tied into it.I replaced the terminal and now it’s good as new.

 

 

Hello Tony,

I too have a code 38 and I think I may have the same problem you had, ground wire problem.  You reference "main access panel". Can you tell me exactly where to look for this?  I'm not sure where you are referring. I'm looking all over for a ground wire problem and not seeing anything.  I thought you may be able to point me to where you problem was so I can look on mine.

Thanks!!!!

Link to comment
Share on other sites

6 hours ago, garland.alford@gmail.com said:

I thought you may be able to point me to where you problem was so I can look on mine.

Welcome to the Escapee forums! 

We may need to go through this process again as TonyGOTR does not appear to have signed into the forums since Feb. 23. If he doesn't respond, there may be others around who would be able to help you.

Good travelin !...............Kirk

Full-time 11+ years...... Now seasonal travelers.
Kirk & Pam's Great RV Adventure

            images?q=tbn:ANd9GcQqFswi_bvvojaMvanTWAI

 

Link to comment
Share on other sites

On 6/10/2020 at 11:23 AM, garland.alford@gmail.com said:

Hello Tony,

I too have a code 38 and I think I may have the same problem you had, ground wire problem.  You reference "main access panel". Can you tell me exactly where to look for this?  I'm not sure where you are referring. I'm looking all over for a ground wire problem and not seeing anything.  I thought you may be able to point me to where you problem was so I can look on mine.

Thanks!!!!

It wasn't actually a ground wire problem at all. It was the controller board failure, which is soldered to the inverter head. 

Call Bob at Parkers Crossroads RV Repair in Parkers Crossroads, TN. He is an Onan whisperer. I found him way after, but he said he fixes them all the time without replacing the entire head. 731.968.9939

2003 International Eagle 9200i, Cummins ISX, Freedomline

2007 Teton Scottsdale XT4

 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...