Circuit/System Testing

Engine running, accessories OFF, measure the battery voltage at the battery terminals. The voltage should be between 12.6 and 15.0 volts.
- If not within the specified range, refer to Charging System Test .
Ignition OFF, disconnect the harness connector at the TBCM.
Ignition OFF, test for less than 5 ohms between the ground circuit terminal 1 and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
Verify that a test lamp illuminates between the B+ circuit terminal 32 and ground.
- If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
If all circuits test normal, replace the TBCM.