Operation CHARM: Car repair manuals for everyone.

Main Relay

Main Relay Testing:




sT=Main Relay Harness Testing:






The main relay contains two individual relays. One relay is energized whenever the ignition is turned on. It supplies power to the ECU, injectors and power for the second relay. The second relay is energized for 2 seconds when the ignition is turned on it also supplies power to the fuel pump when the engine is running.