DTC P1635: 5-Volt Reference A Circuit: Description
WARNING: This page is about a different car, the 2002 Pontiac Montana, 2002 Oldsmobile Silhouette, and 2002 Chevrolet Venture. However, it is still accessible from the selected car via links, so may be relevant.
The PCM uses the 5-volt reference "A" circuit as a sensor feed to the following sensors:
- The TP sensor.
- The MAP sensor.
- The EGR valve pintle position sensor.
The PCM monitors the voltage on the 5-volt reference "A" circuit. If the voltage is out of tolerance, the PCM will set DTC P1635.