Operation CHARM: Car repair manuals for everyone.

Component Tests and General Diagnostics

ECM Power Source Circuit

DESCRIPTION

When the ignition switch is turned to the ON position, the battery voltage is applied to IGSW of the ECM. The output signal from the MREL terminal of the ECM causes a current to flow to the coil, closing the contacts of the EFI relay and supplying power to either terminal +B or +B2 of the ECM.

Wiring Diagram:






Step 1-2:




Step 3-5:




Step 5(Continued)-6:




Step 7-8:




Step 9:




INSPECTION PROCEDURE