Note. For circuit reference, see the appropriate WIRING DIAGRAMS article. For connector and terminal identification, see CONNECTOR IDENTIFICATION .
Circuit Description
PCM uses 5-volt reference "B" circuit as a sensor feed for A/C refrigerant pressure sensor. PCM monitors voltage on this circuit. If PCM senses voltage out of tolerance, DTC P1639 sets.
Conditions required to set DTC are
- PCM detects an out of tolerance condition on the 5-volt reference "B" circuit.
- Listed condition present for longer than 10 seconds