Generator 12 volt

[Robbie_Welch]

I have a 1999 Monaco Windsor with a 7500 diesel generator. I'm having trouble getting the generator to crank over. First off can you tell me witch battery (house or chassis) the generator uses for 12 volt power. Where do the cables make there connection to 12 volt power. I can't seem to locate the generator 12 volt cable at the back of the coach in the electrical compartment for the generator power. Thanks for your help. Robbie

[wolfe10]

In-Vehicle Testing
Tools needed: (a) digital voltmeter, (b) 12V. test lamp.
1. Disconnect the coach from shore power, and kill the engine.
2. Disconnect the wire from the Chassis battery terminal of the LE-415.
3. Connect a 12V. test lamp between the Chassis battery terminal of the LE-415 and chassis ground.
4. Connect a digital voltmeter between the Coach battery terminal of the LE-415 and the Negative terminal of the LE-415.
5. Observe the green LED. If it is OFF, go to step #7.
6. If the green LED is ON, turn on some interior lights to drain the Coach battery until the green LED goes OFF.
7. Connect the coach to shore power and read the digital voltmeter. If it reads 13.5 volts or higher, the green LED should be ON. If it is not ON, the LE-415 should be replaced.
8. If the digital voltmeter reads less than 13.5 volts, start the engine and run it for a few seconds. The charging current from the engine's generator will raise the voltage above 13.5 volts and turn the Model LE-415 ON. If the digital voltmeter reads 13.5 volts or higher, the green LED should be ON. If it is not ON, the LE-415 should be replaced.

[Robbie_Welch]

Well I had the chassis battery load tested and wouldn't you know it a 2 year old battery was bad so that's part of the problem. I need to check the battery maintainer and see if it's working. Anyone know how to test a battery maintainer LE-415 with 3 wires?

[Robbie_Welch]

I think I've got it figured out. The generator uses the chassis battery and it looks like the battery maintainer is not working. I've got a few more things to look into not sure my battery boost solenoid is working as I charged the chassis battery and it went down with the house battery's over night. I can charge the chassis battery with an external charger and start the diesel generator. So I'm good for now. Thanks for the responses Robbie

[wa8yxm]

I do not have your make and model but I suspect it's VIN specific.. Some start of f the house. some the chassis and a very few have a dedicated generator battery.

Today's job.. >Car did not start on its own Wed so had to have park jump it. Jump pack I have.. Well toast.. So today I got new jump pack (Harbor Freight has 'em on sale) then I started checking house batteries .. The twins look ok and once I cleaned the terminals took a charge nicely... They were not thirsty (As anticipated)

The triplets (3 12 volt in parallell) not so good. One (First one) Failed the STATIC test.. Not enough voltage

The 2nd passed with flying color (Green) (load test is 350 amps for 15 seconds actually for a Group 29 that's a bit much)

So one new 31 in position 3
THe one that passed in Position 2
THe one that did not in my car

I'll get a new one tonmorrow and then put the ne (also a 31) in position 2 and the good 29 in position 1 (Easiest to replace)

the third failed the load test (300 amps it could not deliver)

[Executive45]

Your genset operates off the chassis batteries. If yours is like mine, you'll have four ways to start the genset. Try each switch to see if any of them work. Also, have someone stand next to the genset while you crank. You won't hear anything inside the coach. Make sure your disconnects both turned ON. Let us know as you proceed. These are the easiest to check. If these fail, then on to more dirty things.....Dennis

[ksg5000]

Try starting the RV first - this should place both chassis and coach batteries "on-line" and provide max battery power. Having the batteries tested and cleaning both battery and generator grounds is a good idea.

[CA_Traveler]

BTW DC problems can be due to weak batteries. Load test them to make sure they are OK.

[CA_Traveler]

Doesn't crank at all or just slow? Clean all connections - bright shinny clean and tight. The gen ground likely connects to the chassis near the gen. The + may route through the FRP. The RRP should have a large fuse, maybe 200A.

My 10K gen has about 9.5V at 40F when cranking and will get resolved this spring. Batteries are good.

Disconnect the neg on one of the battery banks to determine which bank the gen uses. +

[Flute_Man]

Try using your battery boost switch which ties both sets of batteries together and see if the generator will crank. I had to do that once myself and it worked quite nicely.