Circuit/System Description
WARNING: This page is about a different car, the 2018 GMC Yukon XL, 2018 GMC Yukon, 2018 Chevrolet Tahoe, and 2018 Chevrolet Suburban. 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 engagement actuator consists of a permanent magnetic motor, a worm gear controlled plunger, a front axle switch and an electronic control circuit within the actuator assembly.
The front axle engagement actuator contains the following circuits:
- A Run/Crank Ignition 1 Voltage circuit
- A Four Wheel Drive Wheel Lock Indicator circuit
- An Front Axle Actuator Control circuit
- A ground circuit
When a shift to 4WD Auto, 4WD High or 4WD Low is requested, the transfer case control module engages the front axle by grounding the front axle actuator control circuit through a current limiting driver.