Help troubleshoot RV install

[Gibby]

We bought this RV a couple years ago and it already had a system installed. Late last year I noticed the charge controller wouldn't turn on but decided to wait until spring to check it out. A couple months ago I went to check it and it was working, even rented it out for a few days and it was working. However, now I can not get the charge controller to turn on and the batteries are dead. The battery is showing 1.5v and input from the panels this morning was 43. It is an older EP Solar controller. Is it worth trying to fix or just replace?

 

[TacomaJoe]

You may need to get the battery charged up a little before the MPPT can start doing its thing.

 

[Rednecktek]

If it's lead acid and 1.5v your batteries are shot. If it's LFP and 1.5v then your batteries are so dead that the BMS has gone into protection mode. The charge controller doesn't know there are batteries connected so it's not going to turn on.

Throw a regular battery charger on them or jump them from another power source and they should turn back on which will tell the controller to start charging again.

 

[Gibby]

crap, I was worried about that. I think there are 4 6v batteries, 2 under the steps and 2 in another compartment.

 

[Gibby]

I guess I should have done a visual inspection first.

 

[wme]

Well that sure looks like a good place to start!