P0648

Symptoms

• Check Engine light comes on
• The immobilizer lamp does not light up when the ignition is turned on or is constantly on
• It may be difficult to identify the immobilizer status
• In this case, the engine starts normally (if the immobilizer is working)
• Possible associated immobilizer system codes

Causes

• Broken wire in the immobilizer lamp control circuit
• Burnt-out indicator lamp or faulty LED
• Short circuit in lamp control circuit
• Malfunction of the immobilizer control unit
• Malfunction of the ECU or BCM (body control module)

How to Fix

1. Check the operation of the immobilizer lamp when the ignition is turned on (should be on for ~3 seconds)
2. Check power and ground at the immobilizer control unit
3. Inspect the lamp control circuit wiring
4. Check the fuses associated with the immobilizer system
5. If necessary, diagnose and replace the immobilizer control unit
6. Check for B-codes to clarify diagnosis

Related codes

Error P0648 by Vehicle Brand

FAQ