Operation CHARM: Car repair manuals for everyone.

Cranking Signal: Testing and Inspection

Chart C-1B - Crank Signal:




Wiring Diagram for Chart C-1B - Crank Signal:





CHART C-1B - CRANK SIGNAL

Circuit Description:


The ECM uses crank signal information to provide cranking enrichment when the ECM is in a back-up mode.


Test Description: Numbers below refer to circled numbers on the diagnostic chart.

1. Checks for normal (cranking) voltage to terminal "C9" of ECM. Test light should be "ON" during cranking.


2. Checks to determine if source of blown fuse was a faulty ECM.