P0971 OBD II Trouble Code Pressure Control Solenoid C Control Circuit High

How to quickly diagnose and repair, and causes of a P0971 transmission code that indicates a detected high voltage condition in the C pressure control solenoid control circuit.

Symptoms of P0971 OBD II Trouble Code

  • Increased fuel consumption
  • Check Engine Light activated
  • Transmission overheats
  • Transmission slips when shifting
  • Transmission shifts hard (banging into gear)
  • Possibly misfire-like symptoms
  • The transmission is put into limp mode by the PCM

Common Causes of P0971 OBD II Trouble Code

  • Defective pressure control solenoid
  • Contaminated transmission fluid
  • Restricted transmission filter
  • Defective transmission pump
  • Defective transmission valve body
  • Blocked hydraulic passages
  • Corroded or damaged connector
  • Faulty or damaged wiring
  • Faulty PCM

Severity of P0971 OBD II Trouble Code

The severity of this code normally begins as moderate, but it can progress to a more severe level rapidly when not corrected in a timely manner. In circumstances that result in the transmission banging into gear permanent internal damage can be caused making the problem a severe issue.