Circuit/System Verification
WARNING: This page is about a different car, the 2012 GMC Yukon XL, 2012 GMC Yukon, 2012 Chevrolet Tahoe, and 2012 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
- Verify that the TREC fuse, and the Miscellaneous IGN fuse, underhood fuse block, are not open.
- If the TREC fuse is open, test the battery positive voltage circuit, TCCM harness X3 pin C, for a short to ground.
- If the Miscellaneous IGN fuse is open, test the ignition 1 voltage circuit, TCCM harness X2 pin 6, for a short to ground.
- Ignition ON, engine OFF.
- Using the Freeze Frame feature of the scan tool, review the Battery Voltage parameter when the DTC sets. The voltage should be above 12.0 V.
- If the voltage is above 18.5 V, this is likely a vehicle issue such as an alternator problem, or the vehicle has been hooked up improperly during a jump start. Refer to Symptoms - Engine Electrical .
- If the voltage is below 12.0 V, ensure that the battery is fully charged and working properly. Refer to Battery Inspection/Test ,, Battery Common Causes of Malfunction , and Battery Electrical Drain/Parasitic Load Test .
- Using the Transfer Case Data Display feature of the scan tool, monitor the Battery Voltage parameter. The voltage should be above 12.0 V.
- If the voltage is below 12.0 V, ensure that the battery is fully charged and working properly. Refer to Battery Inspection/Test ,, Battery Common Causes of Malfunction , and Battery Electrical Drain/Parasitic Load Test .
- While monitoring the Battery Voltage parameter, start the engine. Rev the engine to greater than 3000 RPM. The voltage should remain stable and below 18.5 V.
- If the voltage is unstable or is greater than 18.5 V, ensure that the charging system is working properly. Refer to Charging System Test.