DTC P1652: Power Steering Pressure (PSP) Switch: Condition

PSP switch is always on at IAC system monitoring condition. Possible causes are:

Verify Electrical Function

Turn ignition on. Using scan tool, select PSP PID. Observe PID and turn steering wheel left, then right. If PID value does not indicate a change, go to next step. If PID value indicates a change, go to DIAGNOSTIC TEST Z (INTERMITTENT) .

Check PSP Switch Operation

Start and idle engine. Using scan tool, select RPM PID. Disconnect PSP switch connector. If RPM increases, replace PSP switch and repeat QUICK TEST. See TESTS W/CODES - INTRODUCTION article. If RPM does not increase, go to next step.

Check PSP Circuit Resistance

Turn ignition off. Disconnect PCM 104-pin connector. Inspect connector for loose, damaged or corroded terminals. Repair as necessary. Install Breakout Box (014-00950), leaving PCM disconnected. Measure resistance of PSP circuit between test pin No. 31 at breakout box and PSP terminal at PSP switch wiring harness connector. Also, measure resistance of SIG RTN circuit between test pin No. 91 at breakout box and SIG RTN terminal at PSP switch wiring harness connector. If both resistance readings are less than 5 ohms, go to next step. If any resistance reading is 5 ohms or more, repair open in PSP or SIG RTN circuit.

Check For Short In PSP Circuit

Measure resistance between test pins No. 31 and 91 at breakout box. Also, measure resistance between test pin No. 31 and chassis ground. If both resistance readings are 10 k/ohms or more, replace PCM. If any resistance reading is less than 10 k/ohms, repair short circuit.