Section 1571 (Data Link Communications System)
WARNING: This page is about a different car, the 2003 Oldsmobile Bravada, 2003 GMC Envoy XL, 2003 GMC Envoy, and 2003 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
- Schematic and Routing Diagrams
- Component Locator
- Diagnostic Information and Procedures
- Diagnostic Starting Point - Data Link Communications
- Diagnostic Trouble Code (DTC) List
- DTC U1000 And U1255: Node Alive Message Has Not Been Received From An Unidentified Module
- DTC U1001 To U1254: Module U1XXX Communication
- DTC U1300, U1301, or U1305: No Valid Messages Are Detected On The Class 2 Serial Data Circuit
- Symptoms - Data Link Communications
- Scan Tool Does Not Power Up
- Scan Tool Does Not Communicate with Class 2 Device (W/O Immobilizer)
- Scan Tool Does Not Communicate with Class 2 Device (W/ Immobilizer)
- Description and Operation