Circuit/System Testing
WARNING: This page is about a different car, the 2008 GMC Yukon and 2008 Chevrolet Tahoe. However, it is still accessible from the selected car via links, so may be relevant.
- Engine running, accessories OFF, measure and record the battery voltage at the 12V 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 connectors at the appropriate module.
- Ignition OFF and scan tool disconnected, open and close the driver door, and wait 1 minute. Test for less than 5 ohms between the ground circuit 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 12V B+ circuit terminals and ground.
- If the test lamp does not illuminate, test the 12V B+ circuit for a short to ground or an open/high resistance.
- Ignition ON, verify that a test lamp illuminates between the ignition circuit terminals and ground.
- If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
- If all circuits test normal, replace the appropriate module.