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Key Interlock System Circuit Troubleshooting

SRS components are located in this area. Review the SRS component locations (see AIR BAG SRS (SUPPLEMENTAL RESTRAINT SYSTEM) ) , and the precautions and procedures (see AIR BAG SRS (SUPPLEMENTAL RESTRAINT SYSTEM) ) , in the SRS before performing repairs or service.

  1. Turn the ignition switch to ACC (I). The shift lever must be in the P position.
  2. Disconnect the steering lock assembly connector.
  3. Check if the ignition key can be moved to LOCK (0) position, and remove the key from the cylinder.

    Is the ignition key able to move to the LOCK (0) position, and then removed? 

    1. YES  - Go to step 4.
    2. NO  - Replace the ignition key cylinder/steering lock assembly (see STEERING LOCK REPLACEMENT ).
  4. Turn the ignition switch to ACC (I) or ON (II), and shift to the N position.
  5. Check for the voltage between the No. 4 terminal of the steering lock assembly connector and body ground.
    Fig 1: Checking Voltage Between No. 4 Terminal Of Steering Lock Assembly Connector & Body Ground
    G01835855Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  - Go to step 6.
    2. NO  - Check for an open in the (WHT/GRN) wire between the MICU and the steering lock assembly connector. If the wire is Ok, substitute a known-good multiplex integrated control unit and recheck.
  6. Turn the ignition switch to ACC (I), and shift to the P position.
  7. Remove the center console (see CENTER CONSOLE REAR SECTION REMOVAL/INSTALLATION ).
  8. Disconnect the park pin switch connector.
  9. Check for continuity between park pin switch connector terminals No. 1 and No. 4 while pushing the button of the shift lever in, and when released.
    Fig 2: Checking Continuity Between Park Pin Switch Connector Terminals No. 1 & No. 4
    G01835856Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity when pushing the button in, and no continuity when it's released? 

    1. YES  - Check for an open in the wire between the multiplex integrated control unit and the park pin switch connector. If the wire is Ok, replace the multiplex integrated control unit.
    2. NO  - Replace the park pin switch (see Park Pin Switch Replacement  ).