Operation CHARM: Car repair manuals for everyone.

Main Relay (Computer/Fuel System): Description and Operation

SYSTEM OPERATION
As one of its functions, the ASD relay will supply battery voltage to each of the 5 independent ignition coils. The ground circuit for the ASD relay is controlled by the Powertrain Control Module (PCM). The PCM regulates ASD relay operation by switching the ground circuit on-and-off.