Diagnostic Aids
WARNING: This page is about a different car, the 2018 Chevrolet Suburban 3500 HD. However, it is still accessible from the selected car via links, so may be relevant.
P0641
The 5V reference 1 circuit provides 5 V to the sensors listed below:
- Air conditioning (A/C) refrigerant pressure sensor
- Camshaft position sensor
- Engine oil pressure sensor
- Fuel tank pressure sensor
- Throttle inlet absolute pressure sensor
P0651
The 5V reference 2 circuit provides 5 V to the sensors listed below:
- Brake pedal position sensor (automatic transmission)
- Crankshaft position sensor
P0697
The 5V reference 3 circuit provides 5 V to the sensors listed below:
- Accelerator pedal position sensor 2
- Manifold absolute pressure sensor
P06A3
The 5V reference 4 circuit provides 5 V to the sensors listed below:
- Accelerator pedal position sensor 1
- Throttle position sensor 1 and 2
Disconnecting one component at a time from the affected 5V reference circuit while observing the scan tool 5V Reference Circuit Status parameter may help locate the fault. The scan tool parameter will change from Malfunction to OK when the source of the fault is disconnected. If all 5V reference components have been disconnected and a fault is still indicated, the fault may exist in the wiring harness.