Circuit/System Description

The 4WD low circuit is used to notify the powertrain control module (PCM) that the vehicle is in 4WD low range. The PCM supplies 12 volts to this circuit. The transfer case shift control module grounds this circuit when the vehicle is in 4WD low range.

This DTC detects a short-to-ground, short-to-voltage, or an open in the 4WD low circuit.