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 performing repair or service.
- Turn the ignition switch to ACC (I). The shift lever must be in the P position.
- Disconnect the steering lock assembly connector.
- Check if the ignition switch can be turned to the LOCK (0) position.
Can the ignition switch be turned the LOCK (0) position?
YES -Go to step 4.
NO -Replace the ignition key cylinder/steering lock assembly (see STEERING COLUMN/TILT/TELESCOPIC INSPECTION ).
- Turn the ignition switch OFF.
- Move the shift lever out of the P position.
- Check for continuity between steering lock assembly connector terminal No. 3 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Repair short in the wire between the key interlock solenoid and the MICU.
NO -Go to step 7.
- Remove the shift lever assembly (see SHIFT LEVER REMOVAL ).
- Check for continuity between park pin switch/A/T gear position indicator panel light connector terminal No. 3 and body ground.Fig 2: Checking Continuity Between Park Pin Switch/A/T Gear Position Indicator Panel Light Terminal 3 Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Repair short in the wire between park pin switch/A/T gear position indicator panel light connector terminal No. 3 and the MICU.
NO -Go to step 9.
- Shift the shift lever into the P position.
- Check for continuity between park pin switch/A/T gear position indicator panel light connector terminals No. 3 and No. 4. Do not push the shift lever button.Fig 3: Checking Continuity Between Park Pin Switch/A/T Gear Position Indicator Panel Light Terminals 3 And 4
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Faulty park pin switch, replace the park pin switch (see A/T GEAR POSITION INDICATOR PANEL LIGHT HARNESS/PARK PIN SWITCH REPLACEMENT ).
NO -Go to step 11.
- Disconnect under-dash fuse/relay box connector F (34P).
- Turn the ignition switch ON (II).
- Check for voltage between the No. 27 terminal of under-dash fuse/relay box connector F (34P) and body ground.Fig 4: Checking Voltage Between Terminal 27 Of Under-Dash Fuse/Relay Box Connector F (34P) Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there no voltage while the shift lever is in the P position, and is there voltage when the shift lever shifts out of P?
YES -Substitute a known-good MICU and recheck.
NO -Repair or short in the wire between PCM connector terminal B13, transmission range switch, and MICU.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
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.
Rather have a pro handle this?
A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.
No obligation. See pricing before you book.