Diagnostic Aids
WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- The BCM detects that the ignition is ON and sends the appropriate power mode message to the other modules. Therefore, the BCM must be connected to the DLC for any other module to communicate with the scan tool.
- When the class 2 serial data circuit:
- Is shorted to ground
- Is shorted to voltage
The following DTCs may set:
- U1300
- U1301
- U1305