Remove the radio from the dash to access the turn-on wire (usually a blue wire). The turn-on wire will "tell" your amplifier to turn on whenever the receiver is powered up (usually, whenever the vehicle is turned on).
Strip the insulation off a small section of this wire coming from the radio, wrap the blue turn on lead (included with the amp wiring kit) around it, and solder. Or, use crimp connectors and a crimp tool to connect the blue turn on lead to the wire coming from the radio. Wrap the solder or crimp connection with electrical tape (or use a heat gun to apply heat shrink tubing) to guard against a short. Using wire ties (included with the kit) to secure the wire, route the blue turn on lead behind your dash all the way over to the place where the red power wire comes through the firewall.
Making the signal connections
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