Circuit/System Testing
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2008 GMC Yukon XL, 2008 GMC Yukon, 2008 Chevrolet Tahoe, 2008 Chevrolet Suburban, and 2008 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition ON, verify that no generator or battery current sensor DTCs are set that would cause a charging system concern.
- If DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- Ignition OFF, measure the voltage across the battery terminals. The voltage should read 12.0 volts or greater at room temperature.
- If not within the specified value, refer to Battery Inspection/Test .
- Connect a carbon pile tester to the battery.
- Start the engine and increase the engine speed to 2,500 RPM. Observe the voltage reading on the tester. The voltage should read between 12.6-15.0 volts.
- If not within specified range, replace the generator.
- Adjust the carbon pile tester to the specified load test output value, refer to Generator Usage .
- If not within specified value, replace the generator.