Do you have a stock HU or an aftermarket one? If its stock, you have to fing the power ant wire on the stock radio harness and use that to turn on your amp. If you have an aftermarket deck, there should be a blue wire on the harness. Some decks have two blue wires or one blue and one blue/white. One is for the power ant and one is for the amp turn on. Some decks only have one blue wire on them, so just use that one. If all else fails, you can tap into your accessory wire somewhere in the ignition harness or elsewhere to power it up when the car is on..

EDIT: just saw your sig that you have the sony explode deck...this deck i believe has 2 blueish wires, but they should be marked. Use the amp turn on wire..it might be blue/white, but not positive on that..

13.5 @108 MPH-2.2 60ft(stupid FWD!)
S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential
fuel injection)
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