AI Diesel Tech
P0657OBD-IIELECTRICAL

Actuator Supply Voltage A Circuit Open

Common Symptoms

  • Check Engine Light illuminated
  • Various actuators not responding or operating erratically
  • Transmission may not shift properly
  • Engine cooling fan may not operate correctly
  • Electronic throttle control issues or limp mode

Most Likely Root Causes

  • Open circuit in actuator supply voltage wiring harness
  • Corroded or damaged connector pins at PCM or actuator
  • Failed PCM internal power supply circuit
  • Blown fuse or fusible link in actuator supply circuit
  • Damaged wiring from physical contact or heat exposure

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Component Location

Actuator supply voltage circuit originates from the PCM and distributes to multiple actuators throughout the engine compartment and transmission.

Manufacturer Notes

This code indicates a loss of power supply to one or more PCM-controlled actuators and may affect multiple vehicle systems simultaneously.

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