P1651low severityPowertrain
PSP Switch Input Malfunction
on 2002 Ford Thunderbird 3.8L V6 · FWD
What this code means
The Power Steering Pressure switch input to the PCM is not functioning properly. The PCM cannot detect steering load changes.
Symptoms
- Engine stalls when turning at idle or low speed
- Check Engine Light
- No idle speed increase when turning wheel
Common causes
- Faulty PSP switch
- Wiring open or short in PSP circuit
- Low power steering fluid
- Corroded connector
Diagnostic steps
- Test PSP switch with scan tool — verify signal changes when steering
- Check PSP switch connector
- Test wiring continuity
- Check power steering fluid level
Repair notes
Replace PSP switch. Repair wiring. Top off power steering fluid.
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