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2002 FORD THUNDERBIRD
3.9L DOHC V8 (252 hp)•FWD•AUTOMATIC•gas
2 active safety recalls on this vehicle — view recalls
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Repairs0Labor974Torque985Fluid14DTC1870Battery2Maintenance0Recalls2
P1651low severityPowertrain

PSP Switch Input Malfunction

on 2002 Ford Thunderbird 3.9L DOHC V8 (252 hp) · 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

  1. Test PSP switch with scan tool — verify signal changes when steering
  2. Check PSP switch connector
  3. Test wiring continuity
  4. Check power steering fluid level

Repair notes

Replace PSP switch. Repair wiring. Top off power steering fluid.

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