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Power Steering Pressure Switch: Testing and Inspection

P/S Pressure Switch:






1. Disconnect P/S pressure switch connector.
2. Start engine and check for switch continuity with an ohmmeter. While turning the steering wheel, the switch should show continuity. With the steering wheel in the straight ahead position (not being turned), there should be no continuity.
3. If not as specified, replace switch.

Power steering switch input can be checked at ECU terminal 1P. At idle, terminal voltage should be approximately 0V with the switch "ON" and approximately 12V with the switch "OFF."

If terminal voltage is always approximately 0V, check for:

1. Defective switch.
2. Short circuit is wiring from ECU terminal 1P to switch.
3. ECU malfunction.

If terminal voltage is always approximately 12V, check for:

1. Defective switch.
2. Open circuit in wiring from ECU terminal 1P to switch.
3. Bad ground at switch.