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2003 TOYOTA TACOMA
2.7L I4•RWD•AUTOMATIC•gas•3RZ-FE
5 active safety recalls on this vehicle — view recalls
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Repairs0Labor1066Torque2197Fluid17DTC3480Battery2Maintenance0Recalls5
P0978moderate severityPowertrain

Shift Solenoid C Control Circuit Range/Performance

on 2003 Toyota Tacoma 2.7L I4 · RWD

What this code means

The PCM detected that the shift solenoid C control circuit is out of range or performing poorly. This can cause shifting issues.

Symptoms

  • Rough or delayed shifts
  • Gear engagement problems
  • Check engine light on

Common causes

  • Faulty shift solenoid C
  • Corroded or damaged wiring
  • Poor electrical connection
  • Failed PCM/TCM driver

Diagnostic steps

  1. Scan and record freeze frame data
  2. Inspect solenoid connector and wiring
  3. Measure solenoid resistance
  4. Test control circuit voltage and ground
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