Circuit/System Testing
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2011 GMC Yukon XL, 2011 GMC Yukon, 2011 Chevrolet Tahoe, 2011 Chevrolet Suburban, and 2011 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition ON, observe the scan tool BCM Battery Voltage parameter. The reading should be equal to B+ voltage.
- If not the specified value, test the following BCM circuits for an open/high resistance. If the circuits test normal, replace the BCM.
- B+ circuit terminal 3 X3
- Ground circuit terminal 1 X3
- Ground circuit terminal 5 X3
- Ground circuit terminal 9 X4
- Verify that the current sensor is mounted correctly on the negative battery cables. The sensor should be installed with the internal coil around the negative battery cables, with the tape tab pointing away from the battery.
- If the sensor is not installed correctly, remove and reinstall the sensor.
- Ignition OFF, disconnect the harness connector at the battery current sensor.
- Ignition OFF and scan tool disconnected, open and close the driver door, and wait 1 minute. Test for less than 5 ohms between the low reference circuit terminal B and ground.
- If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the BCM.
- Ignition ON, test for 4.5-5.5 volts between the 5-volt reference circuit terminal A and ground.
- If not within the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
- Ignition ON, test for 4.5-5.5 volts between the signal circuit terminal C and ground.
- If not within the specified range, test the signal 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 battery current sensor.