Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
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 ) before doing repairs or service.
- Remove the driver's dashboard lower cover and the lower steering column cover.
- Turn the ignition switch to ACCESSORY (I). The shift lever must be in P.
- Disconnect the steering lock assembly connector.
- Check if the ignition key can be turned to the LOCK (0) position, and remove the key from the cylinder.
Can the ignition key be turned to the LOCK (0) position, and then removed?
YES - Go to step 5.
NO - Replace the ignition key cylinder/steering lock assembly (see STEERING LOCK REPLACEMENT ).
- Turn the ignition switch to ACCESSORY (I) or ON (II), and shift to N.
- Measure the voltage between steering lock assembly connector terminal No. 4 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES - Go to step 7.
NO - Check for an open in WHT/RED ('04-05 models) or WHT ('06-08 models) wire between the multiplex integrated control unit and the steering lock assembly connector. If the wire is OK, substitute a known-good multiplex integrated control unit and recheck.
- Turn the ignition switch to ACCESSORY (I), and shift to P.
- Remove the center console cover (see CENTER CONSOLE REMOVAL/INSTALLATION ).
- Disconnect the transmission gear selection switch/ park pin switch connector.
- Check for continuity between transmission gear selection switch/park pin switch connector terminals No. 1 and No. 4 when the shift lever is in P, and when the shift lever is out of P.Fig 2: Checking Continuity Between Transmission Gear Selection Switch Connector Terminals No. 1 And 4
Courtesy 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?
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.
NO - Replace the park pin switch (see PARK PIN SWITCH REPLACEMENT ).
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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.