LEMON Manuals: Even more car manuals for everyone: 1960-2025
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)) >> Testing >> Immobilizer-Keyless Control Unit Input Test
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Immobilizer-Keyless Control Unit Input Test

WARNING: This page is about a different variant/trim than selected.
NOTE: SRS components are located in this area. Review the SRS component locations - Refer to: SRS Component Location Index (2012), or SRS Component Location Index (2013 - 2015) , and precautions and procedures - Refer to: SRS Precautions and Procedures (2012), or SRS Precautions and Procedures (2013 - 2015) before doing repairs or servicing.
  1. Turn the ignition switch to LOCK (0).
    GHH119391Courtesy of HONDA, U.S.A., INC.
  2. Disconnect the immobilizer-keyless control unit 7P connector - Refer to: Immobilizer-Keyless Control Unit Removal and Installation, or Immobilizer-Keyless Control Unit Registration .
  3. Inspect the connector and socket terminals to be sure they are all making good contact.
    • If the terminals are bent, loose, or corroded, repair them as necessary, and recheck the system.
    • If the terminals are OK, go to step 4.
  4. With the connector still disconnected, do the following input tests:
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, go to step 5.
      Cavity Wire Terminal name Test condition Test: Desired result Possible cause if desired result isnot obtained
      2 LT GRN S-NET Jump the SCS line with the HDS, disconnect PCM connector A (49P) - Refer to: How to Troubleshoot the Fuel and Emissions Systems, or How to Troubleshoot the CVT System Measure the voltage to ground: There should be about 5 V.
      • An open or high resistance in the wire
      • A short to ground in the wire
              Check for continuity between the terminal and PCM connector A (49P) terminal No. 17:There should be continuity. An open or high resistance in the wire
            Disconnect the battery negative terminal Measure the resistance between the terminal and body ground: There should be more than 50 kΩ.
      • Faulty under-dash fuse/relay box
      • Poor ground (G101)
      • An open or high resistance in the ground wire
  5. Reconnect the connector to the immobilizer-keyless control unit, do the following input tests:
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, replace the immobilizer-keyless control unit - Refer to: Immobilizer-Keyless Control Unit Removal and Installation, or Immobilizer-Keyless Control Unit Registration .
      NOTE: After replacing the immobilizer-keyless control unit, do the immobilizer key registration .
      Cavity Wire Terminal name Test condition Test: Desired result Possible cause if desired result isnot obtained
      7 WHT +B_BACK_UP Under all conditions Measure the voltage to ground: There should be battery voltage.
      • Blown No. A29 (10 A) fuse in the under-hood fuse/relay box
      • An open or high resistance in the wire
      6 YEL IG1_FUEL_PUMP Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage.
      • Blown No. B4 (15 A) fuse in the under-dash fuse/relay box
      • An open or high resistance in the wire
      1 BLK LG In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
      • Poor ground (G101)
      • An open or high resistance in the ground wire
      3 LT BLU K_LINE Under all conditions Measure the voltage to ground:There should be pulse voltage (digital signal).
      • Faulty control unit on the K-LINE
      • Short to ground in the K-LINEwire
scientia non olet · About LEMON Manuals