Key Interlock System Circuit Troubleshooting

Disconnect the key switch connector (7P) from the steering lock assembly.
Connect the No. 7 terminal of the key switch connector to the battery positive terminal, and connect the No. 5 terminal to the battery negative terminal.

Fig 1: Connecting The No. 7 Terminal Of The Key Switch Connector To The Battery Positive Terminal, & The No. 5 Terminal To The Battery Negative Terminal
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Turn the ignition switch to ACC (I), then push the ignition key.
Check the key interlock solenoid operation. A clicking sound should be heard while pushing the ignition key, and you should not be able to turn it to the OFF position.
Does the key interlock solenoid operate properly?
1. YES - Go to step 5.
2. NO - Faulty key interlock solenoid/switch. Replace the ignition key cylinder/steering lock assembly.
Measure the voltage between the No. 7 terminal and body ground.

Fig 2: Measuring The Voltage Between The No. 7 Terminal & Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?
1. YES - Go to step 6.
2. NO - Check for a blown No. 47 (20A) fuse in the under-hood fuse/relay box. If the fuse is OK, repair open or short in the wire between the No. 7 terminal of the key switch connector and under-hood fuse/relay box.
Disconnect the park pin switch connector on the shift lever.
With the shift lever in the P position and pulled back toward the driver, check for continuity between the No. 1 and No. 3 terminals of the park pin switch connector.

Fig 3: Checking For Continuity Between The No. 1 & No. 3 Terminals Of The Park Pin Switch Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Go to step 8.
2. NO - Repair open in the wires between the park pin switch and the connector. If the wires are OK, replace the park pin switch.
Check for continuity between the No. 3 terminal of the park pin switch connector and the No. 5 terminal of the key switch connector.

Fig 4: Checking For Continuity Between The No. 3 Terminal Of The Park Pin Switch Connector & The No. 5 Terminal Of The Key Switch Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Go to step 9.
2. NO - Repair open in the wire between No. 3 terminal of the park pin switch connector and the No. 5 terminal of the key switch connector.
Check for continuity between the No. 1 terminal of the park pin switch connector and body ground.

Fig 5: Checking For Continuity Between The No. 1 Terminal Of The Park Pin Switch Connector & Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Check for a loose key switch connector and park pin switch connector. If necessary, substitute a known-good steering lock assembly.
2. NO - Repair open in the wire between the No. 1 terminal of the park pin switch connector and ground (G401), or repair poor ground (G401).