Onan 5500 Starts Briefly Then Stops With Code 32

[Dionmm]

Hgjab Onan 5500 gold Marquis generator.
Was running fine. On a trip, parked a home, connected with 120v 20 amp shore power. Wife started generator while connected to shore power.
Maybe just a coincidence but the generator stopped with an error code 32
( low rpm). I replaced the fuel pump, fuel filter, oil sensor, spark plugs, oil and filter.
It was time for this standard maintenance anyway. Verified spark at both plugs, fuel flow and rotation at generator armature.
verified brushes and contact to armature.
Tried to start with jumper to running 12 volt vehicle. Verified 12volts and ground.
It attempts to start, sprayed starter fluid to ensure that it’s not a fuel issue.
It starts for about 5 seconds then dies with code 32.
Is there a way to check the kill command coming from control board?
I think I am down to two possibilities:
Ignition module or control board.
Anyone with a similar experience?

 

[RayIN]

Does your RV have a ATS/ Automatic Transfer Switch? These switches have multiple contacts inside to switch power sources. This switch is not supposed to be switched from one power source to another under a heavy load.
If any high-draw appliance was operating, it's very likely some contacts are burned and/or stuck together.
That said, the generator breaker should have tripped off if contacts are stuck together.

 

[klook]

I would look at a fuel issue as in low rpm. Replacing those components does not solve a carb problem. I love seafoam in heavy doses, as in disconnect the fuel line and get 100% seafoam in the carb and soak it. recovered 2 outboards in the last week with it. If that fails, take the carb off and clean it or buy a new Chinese one. The original Onan one is $$$

 

[Eagle5]

I would add a second to the Sea Foam. I add one ounce per gallon of gasoline and my Generator works perfectly.

 

[Dionmm]

I will check the contacts on the At.
I will also clean the carb with seafoam.
Will update thread in the next couple of days.

 

[Morich]

Normally not a huge problem but if this generator has a breaker directly on the unit, flipping that off is one way to remove any doubt about issues with the output load being a problem. I think of it as two steps, get the engine running right, then flip the breaker back on to connect any load you might have in the RV. This is a breaker on the output only and not anything involved in starting the generator if like what I have worked.
But always worth checking before trusting. If the generator won't crank with this breaker open, turn it back on and go with what you see, not what I remember!
Also be sure to turn the breaker back on when you want to get power!

 

[Dionmm]

Today’s update. I have the two circuit breakers off, no load on the transfer switches. Checked transfer switch with 30 amp shore power, functioning properly. All 12v circuits are working fine.
I purchased a new carburetor, installed it this morning. Also installed an inline visual fuel filter to visually verify gas flow. Same situation: starts for a few seconds and then dies with a code 32. ( low rpm) I removed the brushes again and verified the armature is rotating. Is there any possibility of a problem with the brushes not registering correctly?
I’m running out of options….control board?

 

[Triss_739]

I had a similar situation, generator ran short period of time and quit. But no codes. After a while it would not start at all. Turned out to be the fuel pump. I guess as it was failing, some fuel was getting through, until it wasn't. Not sure if this helps or not. I am not sure how to check the fuel pump either.

 

[Morich]

Not sure it applies to ALL fuel pumps but what I have seen had a rubber diaphagm that was pulled up and down to pump the fuel. One thing that might fit what you described is a rip in that rubber that gets bigger with use!
This seems a good anwser from Copilot. I see no fatal errors in the info!
Much more info there but this seemed to be the good points?

 

[jkeeblejr]

Have you tried adjusting the governor linkage? I had a similar problem but rpm (and therefore the Hertz) was too high. Onan mother board will shut gen down if too high or too low rpm. Onan manual i found on line shows how to adjust linkage.

 

[Bo Walker]

Make sure there is more than a 1/4 tank of fuel. Otherwise, the generator will not run.,

 

[Dionmm]

Problem exists with full gas tank.
Replaced fuel pump and filter and added a visual filter. I’m positive that the gas flow is excellent.
I will adjust governor linkage to see if it will start.
Still searching for the correct answer.

 

[klook]

Its an Onan, I found your problem.....

 

[Morich]

Snce not too many folks know gensets all that well, I tend to go looking for manuals. It seems you may have done that and know a bit as you've got the right ID for it!
One way I am finding to get a lot of quick suggestions is using one of the AI deals to ask enough questions that it may lead me somewhere.
I have Copilot, so gave it a try and got this:

Are you sure you are not dealing with something really simple like corroded battery cables to let power get to the genset?
But it might also be good to try a few qestions to one of the AI systems as a quick and cheap start? The troubleshooting steps it offers might sound good when all else fails?
You've mentioned the fuel but then it also takes spark, so have you looked at that end of the question?
Running well beyond my experience with them!

 

[Dionmm]

As I stated in my first post I verified spark at both plugs, and connected the generator to a running automobile battery to be sure I have a strong 12v at the generator starter.
I used chat GPT and followed every possible issue that AI suggested. According to GPT I’m at 2 possible problems: control board or ignition module. Based on the strong spark it’s looking like the control board. Before I spend at least $550 I wanted to see if anyone had additional ideas for the solution.

 

[YoYoDaddyOhMy]

As I stated in my first post I verified spark at both plugs, and connected the generator to a running automobile battery to be sure I have a strong 12v at the generator starter.
I used chat GPT and followed every possible issue that AI suggested. According to GPT I’m at 2 possible problems: control board or ignition module. Based on the strong spark it’s looking like the control board. Before I spend at least $550 I wanted to see if anyone had additional ideas for the solution.

My bet is the control board (unfortunately) is your problem. Was it??
As another WGO owner trying to diagnose many issues on a constant basis, AND considering the support available for DIY work is waning in general, I like to check/verify the cause/solution BEFORE spending good money on the repairs (or sending it to a repairman for service) too. I know my limitations, but like doing what I can to be independant from the dealers when I can.

 

[Dionmm]

Unfortunately I had to pause on the generator issue the past few weeks. I will be getting back to it after July 4.