Circuit Description
WARNING: This page is about a different car, the 2007 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
The engine control module (ECM) uses the 5-volt reference 1 circuit as a sensor feed to the following sensors:
- The A/C pressure sensor
- The throttle position (TP) 1 sensor
- The accelerator pedal position (APP) 2 sensor
- The fuel tank pressure (FTP) sensor
If the ECM detects the voltage on the 5-volt reference 1 circuit is outside a valid range, DTC P0641 sets.