So my Pioneer was stolen a while back - I've just put back in the the factory radio, but the front left speaker is out. Any ideas as to how to troubleshoot this? I'm having trouble following the wires through the car. I believe the front lefts are blue/grey and grey/black, is that right?
First, Check the speaker to make sure it isnt blown. Then, attach a speaker or multimeter to the front left channel at the dash, bypassing the stock speaker wire. If Both work then you must have a short in the wire. The factory HU could also be messed up, where did you store it while you had your pioneer? Moisture can do alot of damage to electronics(obviously).
So the speaker appears to be fine. I tested the two wires that run from the plug to the speaker, and they read okay on the multi. I gather that the speaker and wires are okay. I tested the HU itself, and it seemed to read fine also. I may have exhausted my personal resources here. If I were to take it in somewhere, where would you recommend? I got the pioneer installed at circuit city, so that may be my best bet.