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Immobilizer-Keyless Control Unit Input Test

NOTE:
  1. Remove the steering column covers (see COLUMN COVER REMOVAL/INSTALLATION ).
  2. Disconnect the 7P connector (A) from the immobilizer-keyless control unit (B).
    Fig 1: Identifying 7P Connector And Immobilizer-Keyless Control Unit
    G08053868Courtesy of AMERICAN HONDA MOTOR CO., INC.
  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 look 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 Test condition Test: Desired result Possible cause if desired result is not obtained
    3 LT GRN (S-NET) Disconnect PCM connector A (49P) and under-dash fuse/relay box connector Q (14P). Check for continuity between terminal No. 3 and PCM connector A (49P) terminal No. 46:
    There should be continuity.
    An open or high resistance in the wire
    Check for continuity between terminal No. 3 and under-dash fuse/relay box connector Q (14P) terminal No. 9:
    There should be continuity.
    Check for continuity to body ground:
    There should be no continuity.
    A short to ground in the wire
    4 LT GRN (B-CAN) Disconnect under-dash fuse/relay box connector N (45P). Check for continuity between terminal No. 4 and under-dash fuse/relay box connector N (45P) terminal No. 28:
    There should be continuity.
    An open or high resistance in the wire
    Check for continuity to body ground:
    There should be no continuity.
    A short to ground in the wire
    5 ORN (K-LINE) Under all conditions Check for continuity between terminal No. 5 and data link connector (16P) terminal No. 7:
    There should be continuity.
    An open or high resistance in the wire
    Check for continuity to body ground:
    There should be no continuity.
    A short to ground in the wire
  5. Reconnect the connector to the immobilizer-keyless control unit, and 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, the immobilizer-keyless control unit must be faulty; replace it.
    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    1 WHT (VBU) Under all conditions Measure the voltage to body ground:
    There should be battery voltage.
    • Faulty under-dash fuse/relay box
    • Blown No. 4 fuse in the main under-hood fuse box
    • Faulty main under-hood fuse box
    • An open or high resistance in the wire
    2 BRN (IG1) Ignition switch ON (II) Measure the voltage to ground:
    There should be battery voltage.
    • Faulty under-dash fuse/relay box
    • An open or high resistance in the wire
    7 BRN (LG3) In all ignition switch positions Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G101) or an open in the ground wire
    • An open or high resistance in the wire
    • Faulty PCM
    6 PNK (IG KEY SW) Ignition key inserted into the ignition switch Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G601) or an open in the ground wire
    • Faulty under-dash fuse/relay box
    • Faulty ignition key switch
    • An open or high resistance in the wire