So I have a 96 blazer 4 door 4x4 v6. Here recently my headlights and dash lights are flickering but radio is not. It’s aftermarket. My voltage is bouncing from 13-14.7. The gauge it’s self it bouncing to. What could cause this ? Thank you

 

I would guess bad ground or the alternator is on its way out.

 

I went to autozone they tested the alternater and said it was good. Which ground could it be

 

What’s the voltage doing with the engine off but the ignition on and what’s it doing when the truck is running?

George

 

When the engine is off it’s fine it doesn’t bounce

 

What is the voltage when the engine is not running?

George

 

I’m not sure I’m out of town for work right now. I can check when I get back