No DC Power to 5th Wheel

[Northfork Frank]

Installed new batteries, converter tests as running properly, checked reverse polarity fuses, and still no dc power to 5th wheel. Any ideas?

[jsb5717]

What year and model do you have? Does it have a battery disconnect? You might check it to see if it's in the correct position. If you can pull the key out it's off.

[Northfork Frank]

2014 Montana RL3400. Have checked battery disconnect in both positions.

[jimcol]

I'm assuming you have DC when plugged into AC shore power? Sounds like it's time to get the old meter out and start tracing. If you checked the battery disconnect just by operating it I'd start there with my meter. Others have reported the switch going bad regardless of the key position.

[jsb5717]

I agree with Jim. With new batteries you should have functioning 12v to the coach with or without a good converter...as long as the new batteries are charged. If you're plugged into shore power then a functioning converter will power the coach with or without batteries. So if you're sure that the converter is giving full output AND you have fully charged batteries, then the power is being short-stopped somewhere. The cutoff switch is the first place to check. Are there any master fuses to check? Has there been any surges that might have blown the 12v fuses in the control center? Just spit-ballin'

[mhs4771]

You did check the reverse polarity fuses with a meter?? Not just eyeballing them??

[Daryles]

IF...
No DC power from battery. Good when on Shore power.
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.

[rohrmann]

If you have hydraulic leveling on your rig, instead of replacing the 50 amp breaker with another 50 amp breaker, upgrade it to the Lippert recommended 80 amp breaker and this will probably solve your problem.
https://www.amazon.com/Bussmann-CB18...omotive&sr=1-5

[jeririgged223]

Had the same issues a time or two and it turned out to be the GFI in the bathroom. Kept tripping. Replaced it with one from Lowes and never had another problem. Now carry a spare just in case.