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

Main Relay:

PURPOSE
The Engine Control Module (ECM) relay provides operating power to the ECM.

OPERATION
The ECM relay coil receives 12 Volts DC from a fuse link and is grounded through pin 4 of the ECM. When the relay coil is grounded, the contact switch closes and supplies operating 12 Volts DC to pin 47 of the ECM.