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Home >> Suzuki >> 2007 >> Grand Vitara Base, AWD, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 66 (Immobilizer System) >> Diagnostic Information and Procedures >> DTC P1646: ID Code Incorrectness >> Troubleshooting
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DTC P1646: ID Code Incorrectness: Troubleshooting

WARNING: This page is about a different car, the 2008 Suzuki Grand Vitara. However, it is still accessible from the selected car via links, so may be relevant.
TROUBLESHOOTING PROCEDURES

Step Action YES NO
1  Is vehicle equipped with Immobilizer control system?  Go to Step 3. Go to Step 2.
2  CAN communication circuit check 
  1. Disconnect connectors of all control modules communicating by means of CAN.
  2. Check CAN communication circuit between control modules for open, short and high resistance.

Is each CAN communication circuit in good condition? 		 Substitute a known-good ECM and recheck. Repair circuit.
3  Registration of ignition key with ECM 
  1. Register the ignition key with ECM referring to REGISTRATION OF THE IGNITION KEY .

Was registration of ignition key completed? 		 Recheck DTC. Go to Step 4.
4  CAN communication circuit check 
  1. Disconnect connectors of all control modules communicating by means of CAN.
  2. Check CAN communication circuit between control modules for open, short and high resistance.

Is each CAN communication circuit in good condition? 		 Replace ID controller with new one. If DTC P1646 is still detected, substitute a known-good ECM and recheck. Repair circuit.
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