P2684 OBD II Trouble Code Actuator Supply Voltage C Circuit/Open

How to quickly diagnose, repair, and causes of a P2684 diagnostic code which indicates a detected open or general malfunction within the C actuator supply voltage.

Symptoms of P2684 OBD II Trouble Code

  • Poor shifting
  • Lack of torque
  • Stuck in gear
  • CEL (Check engine light) illuminated
  • Overall poor drivability
  • Limited power output
  • Poor fuel mileage
  • Abnormal engine revving/speeds

Common Causes of P2684 OBD II Trouble Code

  • Corroded wire causing high resistance - P2685
  • Internal ECM issue causing excessive supply voltage - P2686
  • Water intrusion
  • Melted/broken connector(s)
  • Short to power
  • General electrical issue (e.g. charging system issue, wrong battery, etc.)

Severity of P2684 OBD II Trouble Code

Severity here is set to moderate, generally speaking. Given the fact that there are multiple code descriptions, you should use caution when diagnosing. Proper service data will be necessary. If this happens to be a transmission code in your case, you definitely want to repair this sooner rather than later. Daily usage of a vehicle with an active transmission code is a risk that we do not want to take.