Onan 5500 generator, stops after a few seconds, shows code 41

[JeffAndPam]

So I have the brushes removed, and I can see the rings. They look a little dark, so I'd like to go ahead and clean them.

I'd rather not order the special cleaning stick and wait for it. Can I use sandpaper for this? If so, what grit?

 

[JeffAndPam]

Update:
I've removed the brushes, they look good. Below is a picture of the slip rings, visible with the brushes removed. Unfortunately the camera left them a bit blurry. They look like they have a dark band on them. From what I've learned (this is all new to me), that doesn't seem good.

I know I can order a "slip stick" from "Flight systems", but rather than wait, is there a home-ready that can be done? Would like to get this back together today.

I saw one post that suggested Scotch-Brite pads. Also I've seen denatured alcohol mentioned.

 

[JeffAndPam]

UPDATE #3:

I managed to clean up the slip rings using Scotch-Brite pads. I no longer got a code 41.

Instead I started getting a Code 36: "ENGINE STOPPED FAULT - Engine stopped without command by controller", then listed such items as check gas level, secure spark plugs.

I fiddled with the spark plug lead wires, pushing them on securely, started again, now I get:

Code 45: "SPEED SENSE FAULT - Controller unable to sense quadrature frequency"

 

[Kevin D Pem]

Quadrature is the forming of a sine wave used for timing,as the fault states. My thoughts are not timing but cycle count to determine frequency of the output.

I could be off on that assumption. It could be the spark tuning via the crank position.

First listed issue is still generator is not producing output. Seems the output is the signal for the governor.

Second possibility would be a sensor likely on the flywheel.

I think it Wise to call cumins onan about the source of the code.

 

[JeffAndPam]

First listed issue is still generator is not producing output. Seems the output is the signal for the governor.

UPDATES #4:
We just took it for a drive, stopped somewhere to test the levelers.
We also tried the generator. This time got the Code 41 again.
It seems to alternate between codes 41 and 45.

With that in mind, is there a possibility it could be the controller board itself?

 

[AbdRahim]

How many hours on it? I would just take it to a reputable Cummins placeand have it serviced. One morning or afternoon - everything upto date and running smoothly.

 

[JeffAndPam]

How many hours on it? I would just take it to a reputable Cummins placeand have it serviced. One morning or afternoon - everything upto date and running smoothly.

It only has 300 hours on it. The nearest Cummins dealer is over an hour away. I was hoping to avoid that trip.
I'm considering pulling out the controller to get a controller number off of it, and see how much a new one is. It might be worth trying to put in a new one first.
BUT, others here are so much smarter about this than I am. I do appreciate all the advice.

 

[AbdRahim]

If it was exercised every month from the time it was new, that is all it has been used in 19 years? If it were mine I would drive the hour and have a thorough service done on it. At that age it may need more stuff than you can find.

 

[Kevin D Pem]

UPDATES #4:
We just took it for a drive, stopped somewhere to test the levelers.
We also tried the generator. This time got the Code 41 again.
It seems to alternate between codes 41 and 45.

With that in mind, is there a possibility it could be the controller board itself?

Sorry! I am in the forest with marginal service. Long weekend always taxes service,so slow will be my response .

I think the board is potted so examination of the board will be a problem. The microprocessor is working or you would have no codes. There could be a bad solder joint, but I would not tell you to replace the board yet, I am not one to throw parts at something to fix the problem!

If you are, then buy a board! I think you will be throwing money away!

Look in the install manual and follow the 12 volt supply wires. Making sure All connections. Are solid on the 12 v+ + side. Then Make sure All groundings straps and busses/ground points are solid and clean.

There is something simple in the power to the armature circuit as to why it is not getting power.

Because I know what to expect, I would jumper maybe 6 volts to the brushes and see if the thing produced power. I might even use a lower voltage. That would likely give a voltage way out of tolerance, so the generator should be isolated to keep damage limited. You may find the field voltage in the trouble shooting section of a field manual.

The only damage it might cause is burn out the board you want to replace so bad. Have a meter on the output and be ready to shut her down.

One more time!!!
Disconnect from the coach if you follow this suggestion.

 

[JeffAndPam]

Thank you Kevin for your detailed reply!

Look in the install manual and follow the 12 volt supply wires. Making sure All connections. Are solid on the 12 v+ + side. Then Make sure All groundings straps and busses/ground points are solid and clean.

I'll start here since that's simple enough.
One question: I recently purchased a product called DeoxIT, as it was suggested by other RV owners to use on electrical connections.
Would it be worth my time to apply that to all connections?