Circuit/System Description

The transfer case shift control module (TCCM) controls the transfer case actuator lock solenoid. The transfer case actuator lock solenoid is released by being energized. This is accomplished by grounding the lock solenoid control circuit during range changes, and 4WD Auto mode. Locking action is applied when power or ground are taken away from the lock solenoid, preventing the transfer case encoder motor (TCEM) from moving. The system is capable of providing a 2WD HI, 4WD HI and 4WD LO lock-up without the need of additional vehicle power to hold the transfer case in these positions.