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Home >> Suzuki >> 2007 >> SX4 Base, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 153 (Immobilizer System) >> Diagnostic Information And Procedures >> DTC P1621: Immobilizer Communication Line Error >> Detecting Condition and Trouble Area
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Detecting Condition and Trouble Area

WARNING: This page is about a different car, the 2007 Suzuki Grand Vitara and 2006 Suzuki Grand Vitara. However, it is still accessible from the selected car via links, so may be relevant.
DETECTING CONDITION AND TROUBLE AREA REFERENCE

Detecting Condition Trouble Area
Communication error between ICM and ECM is detected by ECM.
  • Related fuse(s) blown
  • Poor connection at ICM connector
  • Poor connection at ECM connector
  • Open in power supply wire circuit
  • Open in ground wire circuit
  • Open in communication wire circuits
  • Short to ground wire circuit in communication wire circuits
  • Short to power supply wire circuit in communication wire circuits
  • Short of communication wire circuits
  • ICM faulty
  • ECM faulty