The only Technical Service Bulletin [TSB] that I could find on the stereo unit is in the diagrams down below. I have also included a wiring diagram for the stereo/amplifier for your vehicle along with guides on how to find shorts to grounds in an automotive electrical circuit. You will need to use a Digital Multi-meter [DMM], so here is a link to a guide below explaining how to use one, if needed:
Please go through these guides and get back to us with what you are able to find out.
Images (Click to enlarge)
Saturday, December 21st, 2019 AT 1:23 AM