System Description

BASIC OPERATION STRATEGY
The battery positive voltage in the engine control module is applied through a resistor to the power steering pressure switch. Steering operation causes the power steering fluid pressure to increase, turning the switch on. As a result, continuity is produced between the battery positive terminal and the ground. This causes the power steering fluid pressure terminal voltage to go from high to low. The ECM uses this signal to control idle speed strategy, raising idle speed to compensate for the increased load placed on the engine by the power steering pump when the vehicle is steered at slow speeds.