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P0947high severityPowertrain

Hydraulic Pump Relay Circuit Low

on 2009 Ford Explorer 4.0L V6 SOHC · AWD

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

Other Powertrain codes on this vehicle

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