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Brake 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. Turn ignition switch ON.
4. Measure voltage at terminal 2L.

Condition:--Brake pedal released.
Voltage:--Below 1.0 Volt.

Condition:--Brake pedal depressed.
Voltage:--Battery voltage.

If readings are not as shown, then inspect the brake switch, the wiring between the brake switch and ECM terminal 2L.