Generator starts by itself!

[luckydog1949]

I hope somebody else has experienced, and fixed, this problem before...

We have a 2005 Itasca Horizon with a 7500 watt Onan Quiet Diesel generator. It has been serviced according to the generator manual. We exercise it at least two hours every month.

While plugged in to shore power, and with no problems with the shore power, the generator just started by itself! We've owned the motor home since January 2013 (@ approx 31,000 miles) and have never experienced this before. We now have approx. 46,000 miles on the motor home. The generator has 505 hours on it. The generator does not have an "auto start" feature, as far as I know; and, as far as the motor home owner's manual states.

DW and I were watching TV, relaxing in the coolness of the AC, when the generator cranked itself up and the transfer switch switched over to generator power! It only happened once, so far. We hope that it was just a neighborhood cat, or something, that rested on the switch on top of the generator long enough for the glow plug to cycle and the generator starter to start it, that then ran off. But, I know that's not likely. The starter did not remain engaged when the generator started.

We were a little bit freaked out when it happened!!

Thanks for any information anyone can share.

Tom

[f14av8r]

I would clean and exercise all your start / stop switches (panel, dash, on unit). Use a good contact cleaner from Radio shack or the like. If the problem recurs, you have a short somewhere in the start circuit. Are you SURE you don't have an auto start system?

[Bigd9]

I know you said you were watching TV and plugged into short power, but if you had just arrived and the dash air conditioner was still defrosting this could possibly explain the problem. There have been several reports of sudden start generators on this and other forums. Some of the problems have been traced to the dash board air conditioner dripping melted condenser water directly onto the Onan generator shorting out the electrical components. There are several modifications to redirect the condenser water away from the generator.

[Brockx]

The above advice is all good.

One other thing, at least on a gas unit. The remote start switch completes a ground to make a complete circuit to engage the solenoid that starts the Generator. A wire in the harness going to your remote switch that is "rubbed" bare will start it also.

Other than that, don't Boon-dock in Grave Yards or Native American burial grounds!!!

[Davdeb1]

Mine did the same thing. We were plugged into shore power, sleeping, 4 am. It just started. I've looked at everything, I'm still baffled.

[grtharris]

luckydog1949, been there done that on our 03 Journey. Unplug the control wire connector that is close to the generator. Spray it with some electronic cleaner to get the moisture out then apply some die-electric grease to the contacts and reconnect.

[1ciderdog]

Mine has also started in the middle of the night - the problem was solved as explained in Grant's message above. It hasn't done it after I cleaned that plug - probably three years ago.

[luckydog1949]

Thanks to everyone who replied! I'll try everything suggested. We've been in this site for a while, and haven't run the dash AC. If it happens again, I'll repost.
PS: This could easily have been an ancient Native American burial ground, so I won't write that possibility off....

Tom

[Spizzer]

I've heard that gens have been started by cats climbing on top of it and pushing on the switch. Maybe try wedging something under that rocker switch and see if that stops it.

Jeff

[Dogpatch]

Could it be that you have an RC7 GS controller?

My two Monaco's had that type. It's meant to start automatically when the batteries are sensed as low if set up to do so. Also, If you do, you can set the time it comes on.

[DBTulsa]

Auto gen start, a setting as mentioned above,
on some systems. It is a setting option in the control panel on my ONan 10k

[BT-III]

I had the same situation 2 years ago. Do have an auto start feature but the program was set at off. Plugged to shore power, no AC running, nobody in the coach in fact and the gen starts in the middle of the night. Did nothing to correct the situation, correct what tell me, and it never happen again since.

Do not believe a cat (or similar small animal) could be the culprit. If a cat sits on the switch, the noise from the primer pump would scare the animal who would run away before the genset starts. My thoughts anyway.

So to me the whole affair remains a mystery and I hate mystery when it comes to mechanics, electronics, etc.

Still looking for an answer.