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HOMESERVICE MANUALSHONDA2020CIVIC SI, 4D SEDANREPAIR AND DIAGNOSISBODY & FRAMEDOOR LOCKSSECURITY SYSTEM / KEYLESS ENTRY SYSTEM - TESTING & TROUBLESHOOTINGCHECKIMMOBILIZER SYSTEM CHECK
2020 Honda Civic Si, 4D Sedan

Immobilizer System Check

2020 Honda Civic Si, 4D SedanSECTION Immobilizer System Check

1. Connect the HDS to the data link connector (DLC)

2. Turn the vehicle to the ON mode.

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. If the HDS displays NORMAL N-1, the immobilizer system is OK at this time. If the HDS displays any messages, check as follows:

System Check No. System Check Possible Cause
A-1 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 12 volt battery voltage.
A-2 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 vehicle or for another company's vehicle.
  • 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 12 volt battery voltage.
A-3 No communication between the key and immobilizer-keyless control unit(No transponder detected)
  • The vehicle was turned to the ON mode with a non-immobilizer key.
  • The immobilizer key type is different. It is not for this vehicle but for another vehicle or for another company's vehicle.
  • 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 12 volt battery voltage.
  • Immobilizer-keyless control unit failure
B-1 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 12 volt battery voltage.
  • No communication between the immobilizer-keyless control unit and the PCM because of electrical interference.
  • Open in the IG1 line
B-2 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 12 volt battery voltage.
  • No communication between the immobilizer-keyless control unit and the PCM because of electrical interference.
System Check No. System Check Possible Cause
C-1 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 12 volt 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 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 12 volt 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 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 12 volt 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 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 12 volt 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 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 12 volt 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 The vehicle is turned to the ON mode and to the OFF (LOCK) mode with the registered key.
F-2
F-3
F-4
F-5
RENDER: 1.0x

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