Circuit/System Testing
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- Ignition OFF, disconnect the harness connector at the CHMSL.
- Test for less than 5.0 ohms between the ground circuit terminal B and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
- Connect a test lamp between the control circuit terminal A and the ground circuit terminal B.
- Ignition ON, command the stop lamps ON and OFF by applying and releasing the brake pedal. The test lamp should turn ON and OFF when changing between the commanded states.
- If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
- If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
- If all circuits test normal, replace the CHMSL.