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.
DTC P0641
The 5V reference 1 circuit provides 5 V to the sensors listed below:
- A/C refrigerant pressure sensor
- All four camshaft position sensors
- Engine oil pressure sensor
- Fuel rail pressure sensor
- Fuel tank pressure sensor
- Turbocharger boost/intake air temperature sensor
- Fuel pressure sensor
- Fuel level sensor-primary
- Fuel level sensor-secondary
DTC P0651
The 5V reference 2 circuit provides 5 V to the sensors listed below:
- Brake pedal position sensor
- Crankshaft position sensor
- Multifunction intake air sensor
- Clutch pedal position sensor
- Gear position sensor
- Drive mode select/Vehicle stability control system switch
- Barometric pressure sensor
DTC P0697
The 5V reference 3 circuit provides 5 V to the sensors listed below:
- Accelerator pedal position sensor 2
- Manifold absolute pressure sensor
DTC 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.