P0648 OBD II Trouble Code Immobilizer Lamp Control Circuit

How to easily diagnose, repair, and info on causes of a P0648 trouble code that indicates a detected failure of the immobilizer lamp control circuit.

Symptoms of P0648 OBD II Trouble Code

  • No start
  • Immobilizer lamp inoperative
  • Other stored (security) codes

Common Causes of P0648 OBD II Trouble Code

  • Faulty PCM
  • PCM programming error
  • Open or shorted immobilizer lamp control circuit
  • Defective (dead battery) immobilizer key (fob)
  • Failed immobilizer lamp bulb

Severity of P0648 OBD II Trouble Code

Internal control module codes should be taken seriously. A stored code P0648 (with immobilizer lamp illumination) will likely result in a no start condition.