P0649 OBD II Trouble Code Speed Control Lamp Control Circuit

How to easily diagnose, repair, and info on causes of a P0649 trouble code that indicates a detected failure of the speed control lamp control circuit.

Symptoms of P0649 OBD II Trouble Code

  • Speed control system inoperative
  • Other stored (speed control) codes

Common Causes of P0649 OBD II Trouble Code

  • Faulty PCM
  • PCM programming error
  • Open or shorted speed control lamp control circuit
  • Defective speed control lamp bulb

Severity of P0649 OBD II Trouble Code

All internal control module codes should be taken seriously. A stored code P0649 (with speed control lamp illumination) will likely result in a loss of speed control activation.