Circuit Description
WARNING: This page is about a different car, the 2002 GMC Sierra, 2002 GMC Cab & Chassis Sierra, 2002 Chevrolet Silverado, and 2002 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The front axle control circuit consists of an electric motor actuator which engages and disengages the front axle. The front axle actuator consists of a Permanent Magnetic (PM) motor, a worm gear controlled plunger, a front axle switch and an electronic control circuit all within the actuator assembly.
The front axle actuator has four circuits connected:
- Ignition 3 voltage circuit
- Ground circuit
- Axle actuator control circuit
- Axle switch signal circuit
Whenever a shift to 4HI, or 4LO is requested, the transfer case shift control module engages the front axle by grounding the axle actuator control circuit through a current limiting driver.