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 DTC B1433 is set as current.
- If DTC B1433 is not set as current, operate the vehicle within the Conditions for Setting the DTC.
- Ignition OFF, disconnect each of the following components one at a time. After each component is disconnected, cycle the ignition and verify DTC B1475 remains set as current. The components may be disconnected in any order.
- HVAC module X2
- Windshield washer solvent heater X2 (with RPO XA7)
- If DTC B1433 does not remain set as current, test or replace the last component that was disconnected.
- Ignition OFF, disconnect the X5 harness connector at the BCM.
- Test for greater than 70 ohms of resistance between the BCM ignition 3 voltage circuit terminal 13 and ground.
- If less than specified, test the control circuit for a short to ground. If the circuit tests normal, replace the underhood fuse block.
- If the circuit tests normal, test or replace the BCM.
IMPORTANT:
When cycling the ignition, keep ignition OFF for 5 seconds before checking for current DTC.