Battery issues

[Ban617]

Good evening everyone, I just purchased a new to me 2008 Montana mountaineer 345dbq, first I have to say this is an amazing camper and will fit my family nicely, but I am having an issue with the battery, when I have no battery in the camper and it plugged into my truck all the DC works, unplug my truck and install the battery and no dc power, I metered everything in the battery compartment and have power at all the points I could test, when I check in the electrical panel I have nothing. Now when I plug in the AC power everything works as it should but the battery is only reading battery voltage. Is there a breaker or fuse I am missing?

Thank you everyone

[Foldbak]

Originally Posted by Ban617

Good evening everyone, I just purchased a new to me 2008 Montana mountaineer 345dbq, first I have to say this is an amazing camper and will fit my family nicely, but I am having an issue with the battery, when I have no battery in the camper and it plugged into my truck all the DC works, unplug my truck and install the battery and no dc power, I metered everything in the battery compartment and have power at all the points I could test, when I check in the electrical panel I have nothing. Now when I plug in the AC power everything works as it should but the battery is only reading battery voltage. Is there a breaker or fuse I am missing?

Thank you everyone

Battery disconnect switch on? Big red knob in the battery compartment?

[Carl n Susan]

A 2008 Montana Mountaineer doesn't have a disconnect switch (nor a convenience center). The red self resetting circuit breakers and the most likely cause of this problem.

Check for 13+V on each side of each breaker (check connections to ground) with shore power connected. I believe the 7 Pin plug power supply connects to the Converter side of the red self disconnect CBs. That is why you get 12V from truck cable and the converter. But the battery, and its 12V ,can't pass through one of the CBs (likely the one closest to the battery).

If this isn't it, there a 12V flow chart you can use to trace the power.

[Daryles]

What Carl said.

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

No DC power from battery. Good when on Shore power or connected to truck via 7 way cable.
For a 5th wheel RV...
Take a multimeter. On shore power, check each post of your red 50A self resetting circuit breakers near your batteries. They should all read the same (about 12.4vdc).
Now remove shore power. Check them again.
Which ever one is NOT showing 12vdc on the post, it is bad. Replace it.
Note: charging is also possible via the 7 way cable from your tow vehicle. It could be supplying power on the same (good) side of the breaker.
Buy Bussmann 50A self resetting circuit breakers. Very reliable. You can get them at your local auto parts store.

[Ban617]

I have looked all over and can’t find any breakers for the battery, I will upload a pic of the battery compartment, it is definitely acting as if there is one tripped

[Ban617]

Update, got it working. There was paint under the terminal causing it to have a bad ground, I am sorry for the confusion but thankfull for the help and a fresh set of eyes on this issue

[Carl n Susan]

What terminal had paint under it? The answer may help members in the future,

[Ban617]

The terminal that had paint on it was the new one that was put on the battery, trust me I feel so dumb that I didn’t look there first, but at least it was an easy fix