Power Steering Motor
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2008 GMC Yukon XL, 2008 GMC Yukon, 2008 Chevrolet Tahoe, 2008 Chevrolet Suburban, and 2008 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
The power steering control module (PSCM) responds to the change in the sinusoidal voltage signals of the torque and motor rotational sensors by commanding current to the power steering motor. The motor is attached to the base of the steering gear housing and assists the steering gear pinion to maneuver the rack from left to right according to turning the steering wheel. The 42-volt circuit from the APM supplies power to the pulse width modulated (PWM) motor drive circuit. The motor is a brushless, 3 phase motor with a rated maximum phase current of 40-amps rms.