2004 Acura TL AutomaticFACTORY OEM SERVICE PROCEDURE

Key Interlock System Circuit Troubleshooting

SRS components are located in this area. Review the SRS component locations (see COMPONENT LOCATION INDEX ), and the precautions and procedures (see PRECAUTIONS AND PROCEDURES ), 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 COLUMN/TILT/TELESCOPIC INSPECTION ).
  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 Steering Lock Assembly Connector Terminal 4 And Body Ground
    G03660719Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  - Go to step 6.
    2. NO  - Check for an open in with (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 transmission gear selection switch/park pin switch/A/T gear position indicator panel light connector.
  9. Check for continuity between transmission gear selection switch/park pin switch/A/T gear position indicator panel light connector terminals No. 1 and No. 4 while the shift lever is in the P position, and when the shift lever is out of the P position.
    Fig 2: Checking Continuity Between Transmission Gear Selection Switch Terminals 1 And 4
    G03660720Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity when the shift lever is in any position other than P, and no continuity when the shift lever is in P? 

    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 TEST ).
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.