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Cranking Signal: Testing and Inspection

PREPARATION
Connect the special service tools (SST) to the engine control module (ECM).

Connect Special Service Tools As Shown:





1. Connect the SST engine signal monitor between the ECM and the vehicle's ECM connector by using the SST adapter harness.

View: Special Service Tool (SST)-Sheet Overlay:





2. Place the SST engine signal sheet overlay on the SST engine signal monitor.
3. Measure voltage at terminal 1C under the following conditions.

Condition:--Ignition key-ON.
Voltage:--0.0 Volts.

Condition:--While cranking.
Voltage:--Cranking battery voltage (approx. 10 Volts.)

If readings are not as shown, then inspect the ignition switch, the wiring between the ignition switch and ECM terminal 1C.