CSW 2012 E05 code

[djm560]

I have a 2021 Montana3121RL, when I pulled into the campground and turned my truck off , I heard the inverter beeping. I checked it and an error code E05 was showing and it showed 11.5 volts. A mobile tech said the problem was my truck not charging the batteries . I plugged into shore power and everything works as should. Display show 12.8-13 . After 5 days on shore power , I shut off shore power and after about 20 minutes the inverter started beeping again and the same code came . The fridge was blinking off and on as well . Anyone have any idea where to start ? The tech obviously was wrong.

[Carl n Susan]

It sure sounds like your battery is not connected to the RVs 12V system. I am not sure where you measures the 11.5V after disconnecting from the truck (by the way, don't expect the truck to significantly charge the RV battery) and the 12.8-13 when connected to shore power.

It could be the batteries are shot and won't hold a charge. The converter will produce around 13.5V on shore power so 12.8-13 seems low.

Hopefully you can use a VOM. If so, it is relatively easy to follow the 12V wiring to find where the problem lies.

Thanks to Daryles, here is a link to the diagnosis flowchart. Refer to Post #3 in the Thread https://www.montanaowners.com/forums...ad.php?t=86323