Low Voltage

[wecker1]

We returned from our four months stay in upstate New York last week and as I was backing into the RV garage a message stating something to the effect “trailer electrical failure/error/fault…appeared on the truck dash. It flashed only briefly and then disappeared. While unhooking and trying to auto-level the RV the control panel on the side of the RV presented a low voltage error message, and I had to abort the auto-level. I was able to unhook and level using the manual mode, actuating the stabilizers in short bursts. The control panel stated low voltage in the 11.8 range. I have a 50 Amp hook-up in the garage which I connected to, and nothing improved, the low voltage remained the same. I hooked my truck power cable back to the RV and got a reading of 12.4 volts.

After leveling the RV I left the 50-amp hooked up hoping that it would recharged the system, but to no avail. The voltage continued to drop.

I tested that batteries and one read 6.5 volts and the other about 5.4 volts. I connected the bad battery to an AGM capable charger and let it charge to 100%. When finished the voltage equated to roughly 86% charge on my multimeter…even though the charger stated 100%. Since then and still connected to the 50-amp service the voltage has continued to drop.

I have 2 new (less than 1 year old) 6-volt AGM and while in NY was hooked to 50-amp service without any issues.

I checked the power chord outlet on the rear of the rig but no visible issues. I pulled it out of the rear wall but did not disassemble it…

Thoughts, ideas on how to troubleshoot?

Thanks in advance for your comments and questions.