Agreed. It sounds like whatever you are using for a ground reference in the rear is bad.

 

I wanted to thank you everyone for the suggestions. the problem was the ground wire was grounded in bad spot. After regrounding to a bolt that holds the back seat to floor, everything is working now.


thanks again

 

glad the problem is solved

 

run another ground from your cars battery to the chasis of the car. good practice, I do it on all my installs!!!