Coach 12-volt Electrical Problem Solved

[Metalman]

2015 Windsport 27K

I had no power to any of the 12-volt circuits in the coach unless the generator was running. Running the engine did not produce 12-volts in the coach. The coach batteries were fully charged. I checked the 100 amp resettable circuit breaker and the 50 amp fuse in the battery/hydraulic pump compartment and they both had 12-volts on each side of the devices.

I called Thor and was quickly put in touch with a technician. He had me recheck the fuses and circuit breaker in the battery compartment by checking positive to ground and they were fine. Then he had me check another device located under the dinette seat behind the fuse panel. I measured 12-volts to ground (120 volt steel junction box) on both sides of the device. At this point, the technician was stumped.

Then I touched one of the terminals on the black device under the seat and saw arcing. The nut that secures the ring terminals to the large diameter copper lug was finger-tight. Problem solved.

RV owners might want to check all high amperage 12-volt connections because all the rattling and bouncing our RVs deal with can cause problems.

[Yosemitebob]

Thanks for the info, along with the "fix" few do that I'll keep that in mind.

[gmc]

Vibration affects many things...

Had a neighbors RV last year that had low voltage on the 12v side - after a lot of chasing was a loose ground connection in one of the distribution panels (not a Thor product...)

Last RV I lost 12v except when on shore power - turned out to be loose connections on the battery.

Always something to check for those weird unexplainable problems.

[Metalman]

Some of the guys who run antique vehicles use star washers on critical connections. In my case, I can't imagine that the 1/2" nut loosened only because of vibrations. I suspect it wasn't properly tightened at the factory.

[gmc]

Not just from RV's but other hobbies have shown me just how much vibration can loosen... and how important it is to check those connections (both mechanical and electrical) on a regular basis.

If it were a new RV - I could see it being a factory issue.
Yours appears to be 2 years old - my neighbors was 5... Both appear to me to be beyond the point blaming the factory for a loose connection.

[Metalman]

Originally Posted by vehicle

Not just from RV's but other hobbies have shown me just how much vibration can loosen... and how important it is to check those connections (both mechanical and electrical) on a regular basis.

If it were a new RV - I could see it being a factory issue.
Yours appears to be 2 years old - my neighbors was 5... Both appear to me to be beyond the point blaming the factory for a loose connection.

I think it is unrealistic to expect the owner of any on-road vehicle to be required to check connections on a regular basis. The connections need to be secured in such a way that they remain tight for the duration of the usefulness of the component. That means a star washer, lock washer, jamb nut, lock nut, thread locker, etc. I have been riding motorcycles for more than fifty years and have had very few problems due to loosening of threaded fasteners or connections, and motorcycles vibrate more than motor homes. I believe that if the nut was tightened properly at the factory, I wouldn't have had a problem at 18,000 miles.