12V Lights Not Working on Battery

[coloradoscott]

Hi all,

I'm new to this club and thought it would be a great place to get some advise.

My wife and I just purchased a 2020 Montana High Country 295rl. It's in great shape but I'm having an issue with the interior lights, the pass through storage light, and the 5th wheel light not working while on battery power. Everything works great on shore power, just not while on battery. The control panel doesn't light up either when I open the control panel cabinet door. And lastly, none of the LED lights come on when I remove a fuse in the fuse panel. Assumption is, the LED light comes on when it detects a fault or when the fuse is removed.

I have checked all fuses, even the fuses on the converter which is difficult getting to, and replaced the three Automatic Reset Circuit Breaker near the batteries. Nothing has helped.

Your help is appreciated.

Thanks in advance,
Scott

[twindman]

Make sure the power disconnect switch outside is turned so it can not be removed. It turns off power to MOST 12V things on the rig. You still must disconnect the batter in the battery compartment. Keystone may now be installing a switch up there, but prior years there was nothing, so most of us have added a knife blade switch at the battery post or some other type of switch. If you don't the battery will discharge in 1-2 weeks of just sitting in storage.

[scottz]

Do any other 12V devices work? Slides, refer, water pump? It sounds as if your battery is disconnected or you have a bad battery.

[Daryles]

Carl wrote the perfect troubleshooting flow chart for this problem

https://www.montanaowners.com/forums...ad.php?t=86323

[AZ Traveler]

Scott,

Have you checked your battery bank with a voltmeter to make sure they are charged?

[Foldbak]

Welcome to the MOC and (what they said)

[coloradoscott]

Thanks for the responses everyone. Like I said, this Montana is new to my wife and I so I hope I get a 'pass' on this one?

Hold on to your shorts. After testing everything I could think of, and all the steps mentioned in the 'flow chart', I decided to google 'all 12 volt fixtures not working'. What popped us was a video of an orientation of a similar Montana, that showed where a second battery cutoff was located. Yup, it was the main cutoff valve, located in the compartment where the water hookups were, that was in the engaged position (bypass battery). We purchased this RV sight unseen from Virginia and had it towed to Colorado Springs. We got a very brief orientation of the RV via Zoom so either I missed the part about the second cutoff or they didn't mention it.

Chalk it up to a learning experience. I now know a lot more about this RV than I might have without this experience.

Thanks again everyone,

Sccott

[Carl n Susan]

Yup that "... main cutoff valve, located in the compartment where the water hookups are.." has been the downfall of many. Often referred to is as the "Red Key" it is not really a total disconnect. There are parasitic loads still sucking your 12V even when the Red Key is in the battery disconnect state (i.e. if the Red Key can be removed, the battery is disconnected). The batteries will go dead in roughly a week or so with the batteries disconnected with this device.

You are better off to install a true battery disconnect switch at the battery (preferably the negative pole). The 2022 and later models have eliminated the Red Key with a Giggly Box but the jury is still out on whether that disconnects all parasitic 12V draws.