Lost audio, out of ideas

Pat DiPersia

SCCoA Admin
So I lost audio out of all speakers when I arrived to Carlisle. Worked when I parked the car, didn't work when I started it back up. Started troubleshooting today.

Headunit and speakers are aftermarket. I have the bypass plug in place of the factory amp in the trunk.

Tested out the headunit with one of the new speakers - speaker works fine directly in to the headunit, so I know speaker(s) and headunit are good.

Checked continuity over the amp bypass plug. All wires check out there.

Meter shows AC volts coming over the speaker pair wires to the trunk (And through the amp bypass harness.) Get 1-2 volts when music is playing at top volume. Pause a song - 0 volts. As expected.

Have continuity from the wiring behind the dash, to the trunk, to the right rear speaker harness. Double-checked that I have good continuity from the amp connector in the trunk to the speaker connector.

I do NOT, however, have voltage at the right rear speaker (Didn't try others, yet. . .) Can't figure how I have continuity from the amp harness to the speaker harness, but no voltage. I went through the wiring diagrams, and as far as I can tell, speaker harness comes right off the amp connector - nothing in between.

Am I missing something obvious?

Scott Long

SCCoA Member
None of my SC's have had a factory amp that I am aware of. It may be time consuming but it may be easier to just run new wiring from the head unit to the speakers themselves.

Pat DiPersia

SCCoA Admin
So this was an easy one in the end. Passenger front door speaker - contacts were too close to the door and hitting the metal and I presume shorting out. How it lasted for a month or two THEN started having this issue I have no idea. Had to mount the speaker 180 degrees from how it probably should go (With it's immovable tweeter.) Resolved audio and battery light. Only took too many hours to troubleshoot that one!


SCCoA Member
If it's a Pioneer head unit they are designed to fail safe when sensing an issue like the grounded wire you discovered. There is a process to reset the unit I had the same problem before and did find the fix through searching the issue. Sorry I don't remember the process or where I found it.