Diagnostic Aids
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2012 GMC Yukon XL, 2012 GMC Yukon, 2012 Chevrolet Tahoe, 2012 Chevrolet Suburban, and 2012 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
The 5 V reference 1 circuit provides 5 V to the following sensors:
- Manifold absolute pressure (MAP) sensor
- Fuel tank pressure (FTP) sensor
- Accelerator pedal position (APP) sensor 2
- Engine oil pressure (EOP) sensor
- Air conditioning (A/C) refrigerant pressure sensor
- Camshaft position sensor
The 5 V reference 2 circuit provides 5 V to the following sensors:
- APP sensor 1
- Throttle position sensor 1 and 2
- Crankshaft position sensor
- Brake pedal position sensor
It may be possible to locate the fault by disconnecting one component at a time from the affected 5 V reference circuit while viewing the 5 V Reference circuit status parameter on the scan tool. The scan tool parameter will change from Fault to OK when the source of the fault is disconnected. If all 5 V reference components have been disconnected and a fault is still indicated, the fault may exist in the wiring harness.