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Home >> Suzuki >> 2013 >> SX4 LE, Standard Trans >> Repair and Diagnosis >> External Pages >> Different car >> Section 73 (Immobilizer Control System) >> Diagnostic Information and Procedures >> DTC P1623: Unregistered Transponder >> Troubleshooting
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DTC P1623: Unregistered Transponder: Troubleshooting

WARNING: This page is about a different car, the 2011 Suzuki SX4. However, it is still accessible from the selected car via links, so may be relevant.
P1623: TROUBLESHOOTING CHART

Step Action YES NO
Was "Immobilizer Control System Check" performed?  Go to Step 2. Go to IMMOBILIZER CONTROL SYSTEM CHECK .
DTC check 
  1. Check if any DTC other than P1623 is detected referring to DTC CHECK .

Is DTC other than P1623 detected? 
Go to applicable DTC troubleshooting. Go to Step 3.
Registration of unregistered ignition key with ECM 
  1. Register the unregistered ignition key with ECM referring to REGISTRATION OF THE IGNITION KEY .

Was registration of ignition key completed? 
Recheck DTC. Go to Step 3.
Registration of the spare ignition key 
  1. Register the spare ignition key referring to REGISTRATION OF THE IGNITION KEY .

Was registration of spare ignition key completed? 
Replace ignition key which cannot be registered. Substitute a known-good ECM and recheck.