Solar controller over charging batteries

[philjablonski]

I have a solar controller, GP-PWM-30,  that has started flashing an error that the batteries are overcharged.
I can't figure out how this could happen since it is the controllers job to prevent this from happening.
So I figured the controller has gone bad. 
I replaced it but I'm getting the same issue.
The batteries are two Battle Born lithium batteries.

Any ideas how to debug this issue?

 

[abnorm]

What are the solar panels ?

How long was it working ?

 

[PlethoraOfGuns]

Need specs. Are the batteries actually being overcharged? What voltage is battery at when you get error message? What voltage is the charge controller set at during maximum charging? What is wiring length and gauge from charge controller to battery?

 

[ldsreliance]

Their support page says this can happen if you have too large of a solar panel array with too small of a battery capacity.

But the previous posters are right, we need a lot more information to help diagnose.

 

[philjablonski]

I have two 100 amp Battle Born Lithum batteries.
I have a single 190 watt Go Power solar panel.

The original system was installed in 2017.

 

[Sofisintown]

I have two 100 amp Battle Born Lithum batteries.
I have a single 190 watt Go Power solar panel.

Sounds about right.

I'd say USE some electricity. Boil an egg.
See if the controller still complains after you have discharged the battery some.