Diagnostic Aids
WARNING: This page is about a different car, the 2017 Cadillac ATS. 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:
- A/C refrigerant pressure sensor
- All four camshaft position sensors
- Clutch pedal position sensor (manual transmission)
- Fuel tank pressure sensor
- Fuel rail pressure sensor
- Manifold 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
- Engine oil pressure sensor
- Multifunction intake air sensor
- Vehicle stability control switch
P0697
The 5V reference 3 circuit provides 5 V to the Accelerator pedal position sensor 2
P06A3
The 5V reference 4 circuit provides 5 V to the sensors listed below:
- Accelerator pedal position sensor 1
- Throttle position sensor
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.