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Progressive Power Steering

PPS consists of a speed sensor, Electronic Control Module (ECM), solenoid valve and connecting wiring harness. Signals from the speed sensor are used by the ECM to determine the amount and position of opening for the solenoid valve.

The amount and position of the solenoid valve opening determines the amount of hydraulic assistance to the steering gear. As the vehicle speed is increased, assistance is decreased. As the vehicle speed decreases, assistance increases. The ECM is located in the instrument panel behind the glove box.

Fig 1: Electrical & Hydraulic Circuits of the Progressive Power Steering System
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