Circuit Description
WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. 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 transfer case lock solenoid is released by being energized. This is accomplished by grounding the lock solenoid control circuit during gears shifts, and in the AUTO or adapt mode. Locking action is applied when power or ground are taken away from the lock solenoid, the transfer case motor is prevented from moving. 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.