12V Power Issue 2000 Minnie Winnie Class C

[ctrain22]

I have a 2000 Minnie Winnie Class C. None of the inside 12V lighting, fans, etc work unless plugged into shore power. The slide, steps, work and generator cranks, but nothing else works. I know the slide etc are wired more directly than the lighting system. I have checked all the fuses in the fuse panel. They all seem fine when plugged in. Seems there is a break somewhere between the batteries and the fuse panel. The Aux switch seems to be working as it should. I can here the solenoid click and tested the terminals for power and it works. What would happen if I ran a wire from the batteries to the fuse panel? Maybe with an inline fuse for protection? What would happen if I plugged it in if I did the wiring? Could it cause a short? Thank for your help.

[powercat_ras]

You can find and view the 12 volt wiring diagram for your 2000 Minnie Winnie here.

This shows how the power should be flowing between the batteries and the fuse block. I note that the refrigerator 12 volt power feed is on the same fuse block as the 12V lighting so if your refrigerator is working than there is 12 volt power getting to the fuse block and the problem is NOT the feed to the fuse block unless a prior owner re-wired the RV.

Good luck.

[ctrain22]

Powercat: Thanks for the reply.

The fridge doesn't have power either unless plugged in. Thanks for the wiring diagram. I did already print one but I Just can't seem to follow it. I'll keep studying it.

[powercat_ras]

I copied a key part of the diagram...

I think you need to figure out what is actually wrong and fix it and not jump straight to running a new wire. It would be unlikely it is a bad wire. That said if you had a bad rodent problem it is possible a wire got chewed apart without tripping any fuses or breaker.

The battery fed power goes thru a 30 amp circuit breaker in between two 6 amp breakers to feed the fuse panel that has no power coming from the batteries.

Note that it DOES NOT go directly to the batteries it goes to the battery disconnect relay THEN to the battery.

There is a No. 8 gauge black wire running from the breaker panel near the batteries to the fuse panel. It should be next to a 2nd big black wire that is the feed from the AC-DC converter charger.

I suggest that you disconnect the batteries and unplug from shore power and access the back side of the circuit breaker panel and do some continuity testing. You don't want to remove the panel with the circuit breakers on it with DC power present from batteries or converter charger as it is easy to short something out when you pull out that panel to get access to the back for troubleshooting. You can measure for continuity (indicated by near zero ohms) across the 30 amp circuit breaker and measure continuity across the battery disconnect relay. You could keep measuring continuity to see if one of the wires between the back of the breaker panel have a problem, using a jumper wire to extend one of your volt ohm meter test leads.

[Morich]

On a quick read without going through to look at your specific RV wiring, I would say it is working this way. The RV was turned off with the battery disconnect switch off. This left the coach batteries not getting any chanrge and the parasitic drains left them flat. when you try to use the disconnect switch to turn the coach power back on, the switch is a momentary switch which controls a latching relay. That relay engages/disengages the batteries to the RV.
When the coach batteries are flat, there is no power to move the latching relay and it stays in the disengaged position (turned off?)
You can't turn the coach batteries back on until you have power to move the relay! You may think you have turned it on but it is a momentary switch and does nothing without having power on the coach batteries.

One quick way to get power on those batteries as a test is to start the RV engine. That closes the solenoid to connect the chassis with alternator to the coach . That gives power to THEN press the disconnect switch to engage the coach batteries to the Rv.

If you find you get power for lights, vents and water pump, etc with the engine running, the tells you that the coach batteries are likely too flat to move the relay and they will need to be recharged and/or replaced before things will work right again.

The reason it may work with the engine running is that the flat coach batteries are tied to the chassis and the alternator on the engine will run both chassis and coach items, but likely only as long as the engine is running!

Don't think of batteries as something we put power in one side and draw it out the other as they are more like storage for excess power which we can then use out of storage when needed.
Not a pass through operation but more like an in /out channel at the side.

[Ray,IN]

Nailed it!

[ctrain22]

Update!!

By recommendation from another chat room, It was suggested I look into the small, front, right side, outside storage compartment and find the 12v circuit breaker bank.

When I went in it, low and behold, I found the breaker panel with the 30A breaker popped. I pushed it back in and we now have power. Everything working as normal.

Thank you all for your input and advice.

These forums are priceless.