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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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Repairs0Labor1047Torque1633Fluid17DTC3480Battery2Maintenance0Recalls5
P0947high severityPowertrain

Hydraulic Pump Relay Circuit Low

on 2003 Toyota Tacoma 2.7L I4 · RWD

What this code means

The voltage in the hydraulic pump relay circuit is lower than expected. This often indicates a short to ground or excessive resistance in the circuit.

Symptoms

  • Transmission slipping
  • Transmission warning light on
  • Delayed gear engagement

Common causes

  • Short to ground in relay wiring
  • Faulty pump relay
  • Corroded connector
  • Faulty PCM/TCM

Diagnostic steps

  1. Inspect relay circuit for shorts to ground
  2. Measure circuit voltage with scan tool
  3. Test relay coil resistance
  4. Verify PCM output signal
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