Diagnostic Aids: P0641
WARNING: This page is about a different car, the 2010 GMC Sierra and 2010 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The 5 V reference 1 bus provides 5 V to the following sensors:
- B74 manifold absolute pressure (MAP) sensor
- B150 fuel tank pressure (FTP) sensor
- B1 air conditioning (A/C) refrigerant pressure sensor
- B107 accelerator pedal position (APP) sensor 2
- B37B engine oil pressure (EOP) sensor
- B23 camshaft position sensor
The 5 V reference 2 bus provides 5 V to the following sensors:
- B107 APP sensor 1
- Q38 throttle position sensor 1 and 2
- B26 crankshaft position sensor
- It may be possible to locate the fault by disconnecting one component at a time fro 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 disconcerted. If all 5 V reference components have been disconnected and a fault is still indicated, the fault may exist in the wiring harness.