Circuit Description

When the ignition switch is turned ON, battery positive voltage is applied to the coil which closes the contacts of the EFI main relay (Marked: EFI) and supplies power to terminal +B of the ECM.

This signal causes current to flow to the coil, closing the contacts of the EFI relay and supplying power to terminal +B of the ECM.

If the ignition switch is turned off, the ECM continues to switch on the EFI relay for a maximum of 2 seconds for the initial setting of the throttle valve.