Is there any way to test the polarity of speaker wires from the HU? car came with two speakers but is wired for four. Want to add two more but can't tell + or - on the stock wire harness. Dealer can't help and wiring diagram is not yet available. Can you hook up a VOM and watch the needle sweep to figure out or will that damage HU? I've put in new speakers and there is no bass response (might be out of phase)
i have a 97 cavalier that has 350 watt speakers in the front and 650 watts in the rear including two 12 inch 600 watts and a 2 channel 1400 watt amp and when i turn up the volume the radio shuts off what could be causing this problem. the only speakers connected to the amp is the 12's