Total Electrical Failure After Starting Generator

[Just_Jeff]

Has anyone had this happen before? Any recommendations on fixing it?

Yesterday I went to the RV for a tool and decided to do the monthly of cycle the generator. Here's what I did:

- Turned on the main house power switch
- Turned on the factory-installed inverter by remote because it tells me how many volts the batteries are reading. It said 12.8v. I turned off the inverter.
- Primed the generator by the factory-installed remote switch. It primed, the switch turned red like it's supposed to, so I pushed start.

I heard a thunk...I think it was the generator turning over once, and then nothing. Here are the symptoms:

- No power in the house OR the motor. The only connection between the two should be the auxiliary start switch that lets me start the motor with the house batteries if the motor battery dies, and that wasn't pushed. Even the electric door locks don't work.
- Generator won't prime or turn over even when I use the switch ON the generator instead of the remote.
- RV motor won't turn over. I tried it normally and using the auxiliary start switch, and nothing.
- I checked the inverter one more time and it won't turn on.

I've only made two changes to the electrical system so far.
- New batteries. They use the same battery-to-RV connections as the factory.
- Ran an inverter off the batteries to its own outlet inside the RV. It isn't connected to any of the RV's circuits.

Some of you may remember my previous threads where I bought a whole-house inverter, but real life got in the way and I haven't installed it yet so no changes have been made to the factory electrical system except the new batteries.

To do for today:
- Check the fuse box. (Wasn't convenient yesterday.)
- Check each battery with the voltmeter to see if there's a problem with a single battery.
- Check for critter chewing underneath. We have possums around here, and mice outside, etc.

Any ideas?

[wa8yxm]

Best guess.... Dirty connection on my Chassis battery it is usually the positive but I'd start by checking the negative cable.. both ends.

[MNtundraRet]

First of all most Class C's have the house-batteries used to start the generator.

How cold was it when you tried to start the generator? What do you have for house-batteries? Where the batteries left stored on "disconnect"? How long since last full charge?

Any time the temperature is below freezing the MH engine should be started first and let idle for at least 10 minutes. The alternator should be charging the H-battery(s) with "disconnect" on or off. I normally use the H-battery switch now to energize the solenoid (or solid-state) to connect the batteries.

You should hear the solenoid click to make the connection. They can stick in cold weather and need cycling of the switch a few times. The reason for starting the engine first is that the alternator will raise the voltage sent to H-batteries from 12.6 volts or less (actual bat. voltage) to 14.4 + volts.

The extra voltage is needed to start the generator in cold weather. The generator should be tried to start with the MH engine idling. When the generator is up and running for at least 5 minutes the MH engine could be shut down.

I suspect you new motor-home may have a bad connection or ground somewhere in the starting or charging 12v circuit.

Also; why would you need new batteries 7 months ago on a new 2013 Class C MH? There has to be a problem in the 12 volt circuits that was not addressed by throwing new parts at it.

[beemerphile1]

Clean and tighten cables, check polarity on battery connections.

[Just_Jeff]

And the coldest temps lately have been 18-19F at night. It was around 35-40F when I tried to start the generator.

[Just_Jeff]

I last ran the generator and engine about 6 weeks ago. I installed the batteries about 7 months ago; since then, I've driven from Colorado to Virginia and lived in it for several weeks.

I don't think the batteries are connected to the generator. The generator is on an ATS with shore power before going into the fuse panel, if I understand it correctly. Then the converter runs to the batteries.

[2chiefsRus]

How long has it been since you ran the generator or started the engine before this happened? Did you run either one AFTER you put in the new batteries and the inverter?

[ronfisherman]

What was the outside temperature?
My fist guess would be battery connections at generator.