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Home >> Honda >> 2012 >> Civic HF, Trans Mfr CD MZ2A >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 63 (Security System / Keyless Entry System - Testing & Troubleshooting (Hybrid)) >> Inspection/Adjustment >> Immobilizer System Check
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Immobilizer System Check

WARNING: This page is about a different variant/trim than selected.
  1. Connect the HDS to the data link connector (DLC)

2. Turn the ignition switch to ON (II)

3. Monitor the SYSTEM CHECK in IMMOBILIZER INFO with the HDS.

NOTE  : If the HDS does not communicate with the immobilizer-keyless control unit, check the power, ground, and K-line connections

4. If the HDS displays NORMAL N-1, the immobilizer system is OK at this time and you should refer to the STATUS LOG. If the HDS displays any messages, check as follows:
System Check No. Status log. Indication System Check Possible Cause
A-1 Possible The key is not registered (Incorrect key code)
  • This key is not registered in the immobilizer-keyless control unit. Try to register keys using the HDS.
  • No communication between the antenna and the immobilizer key because of interference from metal such as key chains/key rings/other keys.
  • Low battery voltage.
A-2 Possible Communication error between the key and immobilizer-keyless control unit (Incorrect key code format)
  • Intermittent interruption between transponder and immobilizer-keyless control unit.
  • The immobilizer key type is different. It is not for this vehicle but for another one or for another company's one.
  • Key failure (transponder failure)
  • No communication between the antenna and the immobilizer key because of interference from metal such as key chains/key rings/other keys.
  • Low battery voltage.
A-3 Possible No communication between the key and immobilizer-keyless control unit (No transponder detected)
  • The ignition switch was turned ON (II) with a non-immobilizer key.
  • The immobilizer key type is different. It is not for this vehicle but for another one or for another company's one.
  • Key failure (transponder failure)
  • No communication between the antenna and the immobilizer key because of interference from metal such as key chains/key rings/other keys.
  • Low battery voltage.
  • Immobilizer-keyless control unit failure
B-1 Possible The PCM is not registered
  • The PCM was not registered. Try to register the PCM using the HDS.
  • No communication between the PCM and the immobilizer-keyless control unit because of low battery voltage.
  • No communication between the immobilizer-keyless control unit and the PCM because of electrical interference.
  • Open in the IG1 line
B-2 Possible Error of communication format in PCM (Incorrect registration format)
  • The PCM was not registered. Try to register the PCM using the HDS.
  • No communication between the PCM and the immobilizer-keyless control unit because of low battery voltage.
  • No communication between the immobilizer-keyless control unit and the PCM because of electrical interference.
C-1 Possible Imoes unit is not registered
  • Imoes unit was not registered.
  • No communication between the imoes unit and the immobilizer-keyless control unit because of low battery voltage.
  • No communication between the imoes unit and the immobilizer-keyless control unit because of interference.
  • Try to register the imoes unit with the HDS.
C-2 Possible Error of communication format in imoes unit
  • Imoes unit was not registered.
  • No communication between the imoes unit and the immobilizer-keyless control unit because of low battery voltage.
  • No communication between the imoes unit and the immobilizer-keyless control unit because of electrical interference.
  • Try to register the imoes unit with the HDS.
D-1 Possible S-NET line short
  • S-NET line short from the PCM to the imoes unit or the immobilizer-keyless control unit.
  • No communication between the PCM and the immobilizer-keyless control unit because of low battery voltage.
  • No communication between the immobilizer-keyless control unit and the PCM because of electrical interference.
  • Immobilizer-keyless control unit failure
  • PCM failure
D-2 Possible No communication between imoes unit and immobilizer-keyless control unit (S-NET line)
  • Blown fuse
  • S-NET line open from the imoes unit to the immobilizer-keyless control unit.
  • No communication between the imoes unit and the immobilizer-keyless control unit because of low battery voltage.
  • No communication between the imoes unit and the immobilizer-keyless control unit because of electrical interference.
  • Immobilizer-keyless control unit failure
  • Imoes unit failure
D-3 Possible No communication between PCM and immobilizer-keyless control unit (S-NET line)
  • Blown fuse
  • S-NET line open from the PCM to the immobilizer-keyless control unit.
  • No communication between the PCM and the immobilizer-keyless control unit because of low battery voltage.
  • No communication between the immobilizer-keyless control unit and the PCM because of electrical interference.
  • Immobilizer-keyless control unit failure
  • PCM failure
E-1   Initial registration of immobilizer-keyless control unit is not completed The immobilizer-keyless control unit is not registered. Try to register the immobilizer-keyless control unit using the HDS.
E-2
E-3
E-4
E-5
F-1   Special Mode Turn the ignition switch to ON (II) and to LOCK (0) with the registered key.
F-2
F-3
F-4
F-5
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