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BeeEl · 02-04-2019, 08:27 AM

Hello, What a great place to learn some great info! I can't seem to find an answer to my specific questions so I figured I might as well post the question...starting with my first one.
2007 Coachmen Cross Country
The generator start/stop switch on the dash seems to have a problem, but it appears to be in the circuit. When you press it to start the generator, you can hear the fuel pump come on for priming. It normally starts turning the starter after priming for a few seconds. I can hold down on that button all day and the starter never moves. However, the start/stop switch in the overhead control center over the entry door works as normal. I can start the generator from there. The dash switch will still kill the generator. It worked great a month ago. I make sure I at least run the engine and the generator once a month if I can't get it out and drive it.
I would assume both switches would tie into the same spot on the generator so if one switch works, the other should too. Apparently, that is not the case. I don't even know where to turn. Any ideas?
TIA

Jim_HiTek · 02-04-2019, 09:11 AM

I had the same issue with my generator and after checking all the wiring and connections (all good), found that the PCB on the generator had a pin that had corroded through! That was a surprise as it was just that one pin, but I could see mild corrosion on the others. Plus the board had conformal coat on it for waterproofing. It was a separate pin from the pin that came from the start switch mounted on the genset too.

There was a spare pin in the connector so I rewired the board with a soldered in jumper and moved the incoming switch wire. Good as new.

But that was a '94 Onan generator. Not sure if the '07 generators like yours have the same circuitry. I made up a schematic for my '94 but can't find it atm.

So I'd suggest checking all the connections you can find, and maybe take that board out for inspection.

MSHappyCampers · 02-04-2019, 10:02 AM

Hi ! Welcome to IRV2! We're sure glad you joined the gang!

Wish I could help but that's a new one on me! Have fun and keep her between the ditches!

Good luck, happy trails, and God bless!

BeeEl · 02-04-2019, 10:03 AM

Very good info. I just assumed they would have connected to the same pin. Thank you! I will check that out and report back.

BeeEl · 02-05-2019, 09:28 AM

Well, I found a manual for my model. It states that when the start button is pressed, the controller runs the fuel pump for x seconds and then actuates the starter. That tells me that there is one "start" wire coming from the switch(es). What doesn't make sense is why the switch in question will run the fuel pump (basically step one), but never actuate the starter. However, the other remote switch acts fine.

Bahamaniac · 02-05-2019, 09:36 AM

If you can swap switches see if the problem follows the switch. If it does the switch is bad.

Ray,IN · 02-05-2019, 10:07 PM

Source for new Onan parts and switches.

Jim_HiTek · 02-06-2019, 07:39 AM

Quote:

Originally Posted by BeeEl

Well, I found a manual for my model. It states that when the start button is pressed, the controller runs the fuel pump for x seconds and then actuates the starter. That tells me that there is one "start" wire coming from the switch(es). What doesn't make sense is why the switch in question will run the fuel pump (basically step one), but never actuate the starter. However, the other remote switch acts fine.

Given your symptoms, I seriously doubt that there's anything wrong with the switch itself. I don't know of any two stage switches with a time delay between contact closures. At least not one used in an RV capacity. But the electronics on the control board could easily handly that function.

I'd look at the control board.

BeeEl · 02-06-2019, 08:22 AM

I completely agree with that. The only strange part is one remote switch works and the other works halfway, but they both use the same wire to tie into the genset.

Jim_HiTek · 02-06-2019, 08:42 AM

Quote:

Originally Posted by BeeEl

I completely agree with that. The only strange part is one remote switch works and the other works halfway, but they both use the same wire to tie into the genset.

That sure is strange. What is the brand and model number for the genset? They provided those switches along with the generator when Coachmen ordered it.

With the model number, I might be able to find an electrical drawing and that will help narrow down the issue.

It's a mystery begging for a solution.

2 Stroker · 02-06-2019, 11:57 AM

Quote:

Originally Posted by BeeEl

Hello, What a great place to learn some great info! I can't seem to find an answer to my specific questions so I figured I might as well post the question...starting with my first one.
2007 Coachmen Cross Country
I make sure I at least run the engine and the generator once a month if I can't get it out and drive it.
TIA

Hope you find the problem with your gen-set. It is a good idea to run your gen-set once a month for about 30min under a load but if you can't take your coach out for a good run, let it sleep. It will do more damage to your motor starting and never getting it up to temp to get all the moisture out.
2 stroker

Jim_HiTek · 02-06-2019, 12:07 PM

Quote:

Originally Posted by 2 Stroker

Hope you find the problem with your gen-set. It is a good idea to run your gen-set once a month for about 30min under a load but if you can't take your coach out for a good run, let it sleep. It will do more damage to your motor starting and never getting it up to temp to get all the moisture out.
2 stroker

And I'm happy about that too since mine recently decided not to start when I'm parked. Sounds like a bad ground at the genset. Too cold to crawl under there right now. If I take it out for a drive, and I'll be doing that soon, then it starts OK? Still figuring on that one.

LI-Camper · 02-06-2019, 12:07 PM

I had the same issue with my 2016 Jayco Greyhawk with an Onan generator. The switch in the control center would prime the genny but pushing the start switch would do nothing. I was able to start the genny by using the switch in the genny compartment. The switch in the control center would stop the genny . I looked at the wiring in the genny compartment and found a loose wire (light blue I think) and it was corroded at the end. I saw where it should have been connected. After I cleaned up the wire and place where it belonged, reconnected it and everything worked as it should. So I recommend that you just examine the wiring in the genny compartment. Look for wire(s) that is corroded. This area is somewhat open to the elements. Good luck.

BeeEl · 02-06-2019, 01:34 PM

Genset model is 5.5HDKBA-2733C
I found a service manual with wiring diagram which got me to where I am. The two remote switches come in on the same signal wire so if one works, I would think the other would as well. I broke down and called Cummins and got promoted to "level 2 support". They were very helpful but still unsure as to what would be the problem. The input wire is a ground. The last tech I talked to said he doesn't think it's getting a strong enough signal to start the engine. But again the switching from prime/preheat to start occurs in the board. It is getting the signal but never switches state over to start mode.