Circuit Description
The engine control module (ECM) uses the 5-volt reference circuit as a sensor feed to the following sensors:
- The manifold absolute pressure (MAP)
- The throttle position (TP) sensor 2
- The accelerator pedal position (APP) sensor 2
The ECM monitors the voltage on the 5-volt reference circuit. If the voltage is out of tolerance, the ECM will set DTC P0651.