Circuit/System Verification
- Verify that following BCM DTCs are not present:
- U1814
- U2099
- B1428
- B1370
- B1380
- B1440
- B1441
- If any listed DTC is present, refer to DIAGNOSTIC TROUBLE CODE (DTC) LIST - VEHICLE DIAGNOSTIC INFORMATION to diagnose that DTC prior to this diagnostic.
- Verify that at least 1 module that communicates on high speed GMLAN serial data communicates with the scan tool.
- If no module communicates on high speed GMLAN serial data, refer to SCAN TOOL DOES NOT COMMUNICATE WITH HIGH SPEED GMLAN DEVICE .
- Verify that at least 1 module, excluding BCM, that communicates on low speed GMLAN serial data communicates with the scan tool.
- If no module communicates on low speed GMLAN serial data, excluding BCM, refer to SCAN TOOL DOES NOT COMMUNICATE WITH LOW SPEED GMLAN DEVICE .