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Cranking Signal: Testing and Inspection

Fig. 017 - Wiring Diagram for Chart C-1B Crank Signal. VIN Z:





CHART C-1B

CRANK SIGNAL

ALL ENGINES

FUEL INJECTION (TBI)

Crank signal is a 12V signal to the ECM during cranking to allow enrichment and cancel diagnostics until engine is running or 12V is no longer on circuit.


Fig. 016 Chart C-1B Crank Signal:





1. Checks for normal (cranking) voltage to ECM terminal . Test light should be "ON" during cranking.
2. Checks to determine if source of blown fuse was a faulty ECM.