Chart C1E - PSPS Check
The Power Steering Pressure Switch (PSPS) is a normally closed switch that opens when P/S pressure goes high, such as on a full turn in either direction. When the P/S switch opens, it turns the A/C relay off and sends a signal to the ECM. The ECM uses this signal for idle control.
- A pressure switch that will not close, or an open in circuits No. 495/901 or 450 may cause the engine to stop when power steering loads are high.
- A switch that will not open, or a circuit No. 495/901 shorted to ground, may affect idle quality and will cause the A/C relay to de-energize.NOTE: Test numbers refer to test numbers on diagnostic chart.
- Different makes of "Scan" testers may display the status of this switch in different ways. Refer to "Scan" tester operators manual to determine how this input is indicated.
- Checks to determine if circuit No. 495/901 is shorted to ground.
- This should simulate a closed switch.