Circuit Description
WARNING: This page is about a different car, the 2002 GMC Envoy XL, 2002 GMC Envoy, and 2002 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
The transfer case shift control module controls the Transfer Case Lock Solenoid.
The lock is energized (locking action released, grounding the encoder control circuit) during gear shifts and in AUTO (Adapt) mode operation. When power or ground is removed from the lock solenoid, (locking action applied), the transfer case motor is prevented from moving. In this manner, the system is capable of providing a 2HI, 4HI and 4LO lock-up without the need of additional vehicle power to hold the transfer case in these positions.
This DTC detects an open lock solenoid coil, open motor lock control circuit, or an open motor lock feed circuit.