Shift Interlock Systems: Other Honda Civic GA

KEY INTERLOCK SYSTEM

Key interlock system prevents ignition key from being removed from ignition lock assembly unless shift lever is in Park. When ignition key is in ignition lock assembly, key interlock switch closes, providing voltage to key interlock solenoid and interlock control unit.

If shift lever is not in Park (parking pin switch on), interlock control unit energizes key interlock solenoid by completing ground circuit. When key interlock solenoid is energized, ignition key cannot be removed from ignition lock assembly. Key interlock switch and key interlock solenoid are located on ignition lock assembly. Parking pin switch is located on bottom of shift lever. (Scheme 137)and (Scheme 138).

Scheme 137

Scheme 138

SYSTEM TESTS

Note. Refer to appropriate wiring diagram when checking component wiring. See WIRING DIAGRAMS . To check individual components, see COMPONENT TESTS .

Acura 3.5RL

Note. For circuit identification and component locations, see WIRING DIAGRAMS .

1. Turn ignition on. Depress brake pedal. If brakelights illuminate, go to next step. If brakelights do not illuminate, repair faulty brake switch circuit.
2. Turn ignition off. Disconnect PCM harness connectors "A" and "E". Depress brake pedal. Measure voltage between PCM harness connector "E" terminal No. 2 (Green/White wire) and connector "A" terminal No. 26 (Brown/Black wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open in Green/White wire between brake switch and PCM harness connector "E".
3. Reconnect PCM harness connectors. Disconnect driver's multiplex control unit harness connectors "B" and "C". (Scheme 139) Turn ignition on. Depress brake pedal. Measure voltage between driver's multiplex control unit harness connector "B" terminal No. 26 (White/Green wire) and ground. If battery voltage exists, go to step 5. If battery voltage does not exist, go to next step.
4. Check for open or short in White/Green wire between multiplex control unit harness connector "B" terminal No. 26 (White/Green wire) and PCM harness connector "E" terminal No. 22. Repair as necessary. If White/Green wire is okay, check for loose PCM connectors. Repair as necessary. If PCM connectors are okay, substitute a known-good PCM and retest.
5. Ensure shift lever is in "P" position. Check for voltage between multiplex control unit harness connector "C" terminal No. 2 (Black/Blue wire) and ground. If voltage does not exist, go to next step. If voltage exists, repair open in Black/Blue wire between multiplex control unit harness connector "C" and A/T gear position switch.
6. Turn ignition off. Disconnect shift lock solenoid harness connector. Check for continuity between multiplex control unit harness connector "C" terminal No. 10 (Green wire) and shift lock solenoid harness connector terminal No. 2 (Green wire). If continuity exists, go to next step. If continuity does not exist, repair open in Green wire between multiplex control unit and shift lock solenoid.
7. Connect battery voltage to shift lock solenoid connector terminal No. 1 (Yellow wire) and connect ground to terminal No. 2 (Green wire). If shift lock solenoid operates properly, check for loose driver's multiplex control unit connectors. Repair as necessary. If connectors are okay, substitute a known-good driver's multiplex control unit and retest. If shift lock solenoid does not operate properly, replace shift lock solenoid.

Scheme 139

Honda Accord

Note. For circuit identification and component locations, see WIRING DIAGRAMS .

1. Depress brake pedal. Check brakelights. If brakelights illuminate, go to next step. If brakelights do not illuminate, repair brakelight circuit.
2. Turn ignition on. Place shift lever in "P" position. Depress brake pedal and release accelerator pedal. Measure voltage between PCM harness connector "A" terminal No. 28 (White/Red wire) and ground. If battery voltage exists, check for open or short in White/Red wire between PCM harness connector "A" and driver's multiplex control unit. Repair as necessary. If White/Red wire is okay, check for loose terminal connections. If connections are okay, substitute a known-good driver's multiplex control unit and retest. If battery voltage does not exist, go to next step.
3. Turn ignition off. Disconnect PCM harness connectors "A" and "B". Depress brake pedal. Measure voltage between PCM harness connector "A" terminal No. 32 (White/Black wire) and connector "B" terminal No. 20 or 22 (Brown/Black wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open in White/Black wire between PCM harness connector "A" and brake switch.
4. Reconnect PCM harness connectors "A" and "B". Turn ignition on. Measure voltage between PCM harness connector "C" terminal No. 27 (Red/Black wire) and connector "B" terminal No. 20 or 22 (Brown/Black wire). If about.5 volt exists, go to step 7. If about.5 volt does not exist, go to next step.
5. Turn ignition off. Disconnect TP sensor harness connector. Check continuity between TP sensor harness connector terminal No. 1 (Green/Black wire) and PCM harness connector "B" terminal No. 20 or 22 (Brown/Black wire). If continuity exists, replace throttle body. If continuity does not exist, go to next step.
6. Check for continuity between PCM harness connector "C" terminal No. 18 (Green/Black wire) and PCM harness connector "B" terminal No. 20 (Brown/Black wire) or terminal No. 22 (Brown/Black wire). If continuity does not exist, check for loose PCM connectors. Repair as necessary. If connectors are okay, substitute a known-good PCM and retest. If continuity exists, repair open in Green/Black wire between PCM harness connector "C" and TP sensor.
7. Turn ignition off. Disconnect shift lock solenoid harness connector. Check continuity between shift lock solenoid harness connector terminal No. 2 (Green wire) and driver's multiplex harness connector "B" terminal No. 22 (Green wire). (Scheme 140) If continuity exists, go to next step. If continuity does not exist, repair open in Green wire between driver's multiplex control unit and shift lock solenoid.
8. Turn ignition on. Measure voltage between shift lock solenoid harness connector terminal No. 1 (Yellow wire) and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check for blown fuse No. 9 (7.5-amp) located in underdash fuse/relay box. Replace as necessary. If fuse is okay, repair open or short in Yellow wire between shift lock solenoid harness connector and underdash fuse/relay box.
9. Connect battery voltage to shift lock solenoid harness connector terminal No. 1 (Yellow wire) and connect ground to terminal No. 2 (Green wire). Shift lock solenoid should click. If solenoid operates properly, check for loose connectors at driver's multiplex control unit. Repair as necessary. If connectors are okay, substitute a known-good driver's multiplex control unit and retest. If solenoid does not operate properly, replace shift lock solenoid.

Scheme 140

Honda CR-V

Note. For circuit identification and component locations, see WIRING DIAGRAMS .

1. Depress brake pedal. Check brakelights. If brakelights illuminate, go to next step. If brakelights do not illuminate, repair brakelight circuit.
2. Turn ignition on. Place shift lever in "P" position. Depress brake pedal and release accelerator pedal. Measure voltage between PCM harness connector "A" terminal No. 28 (White/Red wire) and ground. If battery voltage does not exist, go to next step. If battery voltage exists, check for open or short in White/Red wire between PCM harness connector "A" and interlock control unit. Repair as necessary. If White/Red wire is okay, check for loose connectors. If connectors are okay, substitute a known-good interlock control unit and retest.
3. Turn ignition off. Disconnect PCM harness connectors "A" and "B". Measure voltage between PCM harness connector "A" terminal No. 32 (Green/White wire) and connector "B" terminal No. 20 or 22 (Brown/Black wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open in Green/White wire between PCM harness connector "A" and brake switch.
4. Reconnect PCM harness connectors "A" and "B". Turn ignition on. Measure voltage between PCM harness connector "C" terminal No. 27 (Red/Black wire) and connector "B" terminal No. 20 or 22 (Brown/Black wire). If about .5 volt exists, go to step 7 . If about .5 volt does not exist, go to next step.
5. Turn ignition off. Disconnect TP sensor harness connector. Check for continuity between TP sensor harness connector terminal No. 1 (Green/Black wire) and PCM harness connector "B" terminal No. 20 or 22 (Brown/Black wire). If continuity exists, ensure TP sensor is correctly installed. If continuity does not exist, go to next step.
6. Check for continuity between PCM harness connector "C" terminal No. 18 (Green/Black wire) and connector "B" terminal No. 20 or 22 (Brown/Black wire). If continuity does not exist, check for loose PCM connectors. Repair as necessary. If connectors are okay, substitute a known-good PCM and retest. If continuity exists, repair open in Green/Black wire between PCM harness connector "C" and TP sensor.
7. Turn ignition off. Disconnect shift lock solenoid harness connector. Check for continuity between shift lock solenoid harness connector terminal No. 2 (Yellow/Black wire) and interlock control unit harness connector terminal No. 3 (Yellow/Black wire). If continuity exists, go to next step. If continuity does not exist, repair open in Yellow/Black wire between interlock control unit and shift lock solenoid.
8. Turn ignition on. Measure voltage between shift solenoid harness connector terminal No. 1 (Yellow wire) and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check for blown fuse No. 25 (7.5-amp) located in underdash fuse/relay box. Replace as necessary. If fuse is okay, repair open or short in Yellow wire between shift lock solenoid harness connector and underdash fuse/relay box.
9. Connect battery voltage to shift lock solenoid harness connector terminal No. 1 (Yellow wire) and connect ground to terminal No. 2 (Yellow/Black wire). Shift lock solenoid should click. If solenoid operates properly, check for loose connectors at interlock control unit. Repair as necessary. If connectors are okay, substitute with a known-good interlock control unit and retest. If solenoid does not operate properly, replace shift lock solenoid.

Honda Odyssey

Note. For circuit identification and component locations, see WIRING DIAGRAMS .

1. Depress brake pedal. Check brakelights. If brakelights illuminate, go to next step. If brakelights do not illuminate, repair brakelight circuit.
2. Turn ignition on. Place shift lever in "P" position. Depress brake pedal and release accelerator pedal. Measure voltage between PCM harness connector "A" terminal No. 28 (White/Red wire) and ground. If battery voltage exists, check for open or loose terminal connections in White/Red wire between PCM harness connector "A" and driver's multiplex control unit. Repair as necessary. If okay, substitute a known-good driver's multiplex control unit and retest. If battery voltage does not exist, go to next step.
3. Turn ignition off. Disconnect PCM harness connectors "A" and "B". Depress brake pedal. Measure voltage between PCM harness connector "A" terminal No. 32 (White/Black wire) and connector "B" terminal No. 20 or 22 (Brown/Black wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open in White/Black wire between PCM harness connector "A" and brake switch.
4. Reconnect PCM harness connectors "A" and "B". Turn ignition on. Measure voltage between PCM harness connector "C" terminal No. 27 (Red/Black wire) and connector "B" terminal No. 20 or 22 (Brown/Black wire). If about.5 volt exists, go to step 7. If about.5 volt does not exist, go to next step.
5. Turn ignition off. Disconnect TP sensor harness connector. Measure voltage between TP sensor connector terminals No. 1 (Green/Black wire) and No. 3 (Yellow/Blue wire). If voltage is about.5 volt, repair short or open in Red/Black wire between PCM harness connector "C" terminal No. 27 and TP sensor connector terminal No. 2. If Red/Black wire is okay, replace PCM. If voltage is not about.5 volt, go to next step.
6. Check for continuity between TP sensor connector terminal No. 1 (Green/Black wire) and ground, and between terminal No. 3 (Yellow/Blue wire) and ground. If continuity exists, repair short to ground in appropriate wire. If continuity does not exist, go to next step.
7. Turn ignition off. Disconnect shift lock solenoid harness connector. Check for continuity between shift lock solenoid harness connector terminal No. 2 (Green wire) and driver's multiplex harness connector "B" terminal No. 22 (Green wire). (Scheme 140) If continuity exists, go to next step. If continuity does not exist, repair open in Green wire between driver's multiplex control unit and shift lock solenoid.
8. Turn ignition on. Measure voltage between shift solenoid harness connector terminal No. 1 (Yellow/Black wire) and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check for blown fuse No. 9 (10-amp) located in underdash fuse/relay box. Replace as necessary. If fuse is okay, repair open or short in Yellow/Black wire between shift lock solenoid harness connector terminal No. 1 and underdash fuse/relay box.
9. Connect battery voltage to shift lock solenoid harness connector terminal No. 1 (Yellow wire) and connect ground to shift lock solenoid harness connector terminal No. 2 (Green wire). Shift lock solenoid should click. If solenoid operates properly, go to next step. If solenoid does not operate properly, replace shift lock solenoid.
10. Check for loose connectors at driver's multiplex control unit. Repair as necessary. If connectors are okay, substitute a known-good driver's multiplex control unit and recheck system. If symptom or problem goes away, replace driver's multiplex control unit.

Honda Prelude

Note. For circuit identification and component locations, see WIRING DIAGRAMS .

1. Ensure Malfunction Indicator Light (MIL) is not illuminated. If MIL is illuminated, diagnose PGM-FI system first. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. Turn ignition on. Depress brake pedal. If brakelights illuminate, go to next step. If brakelights do not illuminate, repair brakelight circuit.
2. Turn ignition off. Disconnect TCM harness connectors "A" and "B". TCM is located under carpet on right front footwell, next to ECM. Depress brake pedal. Measure voltage between TCM harness connector "B" terminal No. 12 (White/Black wire) and connector "A" terminal No. 13 or 26 (Brown/Black wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open in White/Black wire between TCM harness connector "B" and brake switch.
3. Reconnect TCM harness connectors "A" and "B". Disconnect passenger's multiplex control unit harness connector "A". Turn ignition on. Depress brake pedal. Measure voltage between passenger's multiplex control unit harness connector terminals No. 13 (White/Green wire) and No. 14 (Black wire). If battery voltage exists, go to next step. If battery voltage does not exist, check for open or short in White/Green wire between passenger's multiplex control unit harness connector "A" and TCM harness connector "A". Repair as necessary. If White/Green wire is okay, check for poor ground or loose TCM connectors. Repair as necessary. If ground and connectors are okay, substitute a known-good TCM and retest.
4. Place shift lever in "P" position. Measure voltage between passenger's multiplex control unit harness connector terminals No. 14 (Black wire) and No. 16 (Black/Blue wire). If voltage exists, repair open in Black/Blue wire between passenger's multiplex control unit and A/T gear position switch. If voltage does not exist, go to next step.
5. Disconnect shift lock solenoid harness connector. Turn ignition on. Measure voltage between shift lock solenoid harness connector terminal No. 1 (Yellow/Red wire) and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check for blown fuse No. 18 (7.5-amp) located in underdash fuse/relay box. Replace fuse as necessary. If fuse is okay, repair open in Yellow/Red wire between shift lock solenoid connector and underdash fuse/relay box.
6. Turn ignition off. Check for continuity between passenger's multiplex control unit harness connector terminal No. 15 (Green/Yellow wire) and shift lock solenoid harness connector terminal No. 2 (Green/Yellow wire). If continuity exists, go to next step. If continuity does not exist, repair open in Green/Yellow wire between passenger's multiplex control unit and shift lock solenoid.
7. Connect battery voltage to shift lock solenoid harness connector terminal No. 1 (Yellow/Red wire) and connect ground to shift lock solenoid harness connector terminal No. 2 (Green/Yellow wire). Shift lock solenoid should click. If shift lock solenoid operates properly, go to next step. If solenoid does not operate properly, replace shift lock solenoid.
8. Check for loose passenger's multiplex control unit connectors. Repair as necessary. If connectors are okay, substitute a known-good passenger's multiplex control unit and retest.

Note. For circuit identification and component locations, see WIRING DIAGRAMS .

1. Turn ignition off. Disconnect 8-pin steering lock harness connector located near lower left of steering column. Connect steering lock harness connector terminal No. 5 (Black/Red wire) to battery voltage and terminal No. 4 (White/Red wire) to battery ground. A clicking sound should be heard from key interlock solenoid. If interlock solenoid operates properly, go to next step. If interlock solenoid does not operate properly, replace ignition key cylinder/steering lock assembly. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
2. Connect steering lock harness connector terminal No. 8 (White/Green wire) to battery voltage and terminal No. 4 (White/Red wire) and ground. Turn ignition switch to ACC position. Push in on ignition key. A clicking sound should be heard from key interlock solenoid when key is pushed in. If key interlock solenoid operates properly, go to next step. If key interlock solenoid does not operate properly, replace ignition key cylinder/steering lock assembly. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
3. Disconnect driver's multiplex control unit harness connectors "A" and "C". (Scheme 139) Check for continuity between multiplex control unit harness connector "A" terminal No. 2 (Black/Red wire) and ground, and between terminal No. 13 (White/Red wire) and ground. If continuity exists, repair short in appropriate wire between multiplex control unit harness connector "A" and steering lock harness connector. If continuity does not exist, go to next step.
4. Check for continuity between driver's multiplex control unit harness connector "C" terminal No. 5 (White/Black wire) and ground. If continuity does not exist, go to next step. If continuity exists, check for short in White/Black wire between multiplex control unit harness connector "C" and parking pin switch. If White/Black wire is okay, check or replace parking pin switch. See «PARKING PIN SWITCH»(ref-121437-S24411774922001083000000) under REMOVAL & INSTALLATION.
5. Turn ignition on. Check for voltage between driver's multiplex control unit harness connector "C" terminal No. 2 (Black/Blue wire) and ground. If voltage does not exist, check for loose driver's multiplex control unit connectors. Repair as necessary. If connectors are okay, substitute a known-good driver's multiplex control unit and retest. If voltage exists, repair open in Black/Blue wire between multiplex control unit harness connector "C" and A/T gear position switch.

Note. For circuit identification and component locations, see WIRING DIAGRAMS .

1. Turn ignition off. Disconnect 7-pin steering lock harness connector located near lower right side of steering column.
2. Connect steering lock harness connector terminal No. 7 (White/Yellow wire) to battery voltage and terminal No. 5 (White/Red wire) to ground. Turn ignition switch to ACC position. Push in on ignition key. A clicking sound should be heard from key interlock solenoid. If interlock solenoid operates properly, go to next step. If interlock solenoid does not operate properly, replace ignition key cylinder/steering lock assembly. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
3. Measure voltage between steering lock harness connector terminal No. 7 (White/Yellow wire) and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check for blown fuse No. 47 (20-amp) located in underhood fuse/relay box. Replace as necessary. If fuse is okay, repair open in White/Yellow wire between steering lock harness connector and underhood fuse/relay box.
4. Disconnect parking pin switch harness connector. Parking pin switch is located on front side of shift lever. Place shift lever in "P" position. Check for continuity between parking pin switch harness connector terminals No. 3 (Black wire) and No. 4 (White/Black wire). If continuity exists, go to next step. If continuity does not exist, check for open in wires between parking pin switch and 4-pin harness connector. Repair as necessary. If wires are okay, replace parking pin switch.See «PARKING PIN SWITCH»(ref-121437-S24411774922001083000000) under REMOVAL & INSTALLATION.
5. Check for continuity between parking pin switch harness connector terminal No. 4 (White/Red wire) and steering lock harness connector terminal No. 5 (White/Red wire). If continuity exists, go to next step. If continuity does not exist, repair open in White/Red wire between parking pin switch and steering lock harness connector.
6. Check for continuity between parking pin switch harness connector terminal No. 3 (Black wire) and ground. If continuity exists, check for loose key interlock switch connector and parking pin switch connector. Repair as necessary. If connectors are okay, substitute a known-good steering lock assembly and retest. If continuity does not exist, repair open in Black wire between parking pin harness connector and ground.

Note. For circuit identification and component locations, see WIRING DIAGRAMS .

1. Turn ignition off. Disconnect 6-pin steering lock harness connector located behind left side of dash. Connect steering lock harness connector terminal No. 4 (White wire) to battery voltage and connect terminal No. 3 (White/Blue wire) to ground. A clicking sound should be heard from key interlock solenoid. If key interlock solenoid operates properly, go to next step. If key interlock solenoid does not operate properly, replace ignition key cylinder/steering lock assembly. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
2. Connect steering lock harness connector terminal No. 5 (White/Green wire) to battery voltage and terminal No. 3 (White/Blue wire) to ground. Turn ignition switch to ACC position. Push in on ignition key. A clicking sound should be heard from key interlock solenoid. If interlock solenoid operates properly, go to next step. If interlock solenoid does not operate properly, replace ignition key cylinder/steering lock assembly. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
3. Disconnect interlock control unit harness connector. Check for continuity between interlock control unit harness connector terminal No. 1 (White/Blue wire) and ground, and between terminal No. 5 and ground. If continuity does not exist, go to next step. If continuity exists, repair short in appropriate wire between interlock control unit and steering lock harness connector.
4. Check for continuity between interlock control unit harness connector terminal No. 8 (White/Black wire) and ground. If continuity does not exist, go to next step. If continuity exists, repair short in White/Black wire between interlock control unit and parking pin switch.
5. Turn ignition on. Place shift lever in Park. Measure voltage between interlock control unit harness connector terminal No. 6 (Black/Blue wire) and ground. If voltage does not exist, check for loose connectors. Repair as necessary. If connectors are okay, substitute a known-good interlock control unit and retest. If voltage exists, repair open in Black/Blue wire between interlock control unit and parking pin switch.

Note. For circuit identification and component locations, see WIRING DIAGRAMS .

1. Turn ignition off. Disconnect 7-pin steering lock harness connector located on right side of steering column.
2. Connect steering lock harness connector terminal No. 7 (White/Yellow wire) to battery voltage and terminal No. 5 (White/Red wire) to ground. Turn ignition switch to ACC position. Push in on ignition key. A clicking sound should be heard from key interlock solenoid. If key interlock solenoid operates properly, go to next step. If key interlock solenoid does not operate properly, replace ignition key cylinder/steering lock assembly. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
3. Measure voltage between steering lock harness connector terminal No. 7 (White/Yellow wire) and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check for blown fuse No. 47 (20-amp) located in underhood fuse/relay box. Replace as necessary. If fuse is okay, repair open in White/Yellow wire between steering lock harness connector and underhood fuse/relay box.
4. Disconnect parking pin switch harness connector. Parking pin switch is located at top of steering column. With shift lever in "P" position and pulled toward driver, check for continuity between parking pin switch harness connector terminals No. 1 (Red wire) and No. 3 (Black wire). If continuity exists, go to next step. If continuity does not exist, repair open in appropriate wire between parking pin switch and harness connector. Repair as necessary. If wires are okay, replace parking pin switch. See «PARKING PIN SWITCH»(ref-121437-S24411774922001083000000) under REMOVAL & INSTALLATION.
5. Check for continuity between parking pin switch harness connector terminal No. 3 (White/Red wire) and steering lock harness connector terminal No. 5 (White/Red wire). If continuity exists, go to next step. If continuity does not exist, repair open in White/Red wire between parking pin switch and steering lock connector.
6. Check for continuity between parking pin switch harness connector terminal No. 1 (Black wire) and ground. If continuity exists, check for loose ignition key switch harness connector and parking pin switch connector. Repair as necessary. If connectors are okay, substitute a known-good steering lock assembly and retest. If continuity does not exist, repair open in Black wire between parking pin harness connector and ground.

Note. For circuit identification and component locations, see WIRING DIAGRAMS .

1. Disconnect steering lock harness connector located behind dash, on lower left side steering column. Connect battery voltage to steering lock harness connector terminal No. 5 (White/Yellow wire) and connect ground to terminal No. 3 (White/Red wire). Turn ignition key to ACC position. Push in on ignition key. A clicking sound should be heard from key interlock solenoid. If key interlock solenoid and switch operates properly, go to next step. If key interlock solenoid or switch does not operate properly, replace ignition key/cylinder lock assembly. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
2. Reconnect steering lock harness connector. Disconnect mode switch 8-pin harness connector located below center console. (Scheme 141) Turn ignition switch to ACC position. Check voltage between mode switch harness connector terminal No. 8 (White/Red wire) and ground while pushing in on ignition key. If voltage exists, go to next step. If voltage does not exist, repair open in White/Red wire between mode switch harness connector and steering lock connector.
3. Check for continuity between mode switch harness connector terminal No. 3 (Black/White wire) and ground. If continuity exists, replace mode/parking pin switch assembly. See «PARKING PIN SWITCH»(ref-121437-S24411774922001083000000) under REMOVAL & INSTALLATION. If continuity does not exist, repair open in Black/White wire between mode switch harness connector and ground connector.

Scheme 141

Note. For circuit identification and component locations, see WIRING DIAGRAMS .

1. Turn ignition on. Check if "D4" indicator light on instrument panel is flashing. If D4 indicator light is flashing, diagnose A/T electronic control system. See appropriate ELECTRONIC CONTROLS article. If "D4" indicator light is not flashing, go to next step.
2. Place shift lever in "P" position. Measure voltage between passenger's multiplex control unit harness connector terminals No. 14 (Black wire) and No. 16 (Black/Blue wire). If voltage does not exist, go to next step. If voltage exists, repair open in Black/Blue wire between multiplex control unit harness connector and A/T gear position switch. See «WIRING DIAGRAMS»(ref-121437-S12285601742001082500000) .
3. Turn ignition off. Disconnect passenger's multiplex control unit harness connector. Turn ignition on. Place shift lever in "N" position. Check voltage between passenger's multiplex control unit harness connector terminals No. 14 (Black wire) and No. 15 (Green/Yellow wire). If voltage does not exist, go to next step. If voltage exists, repair open in circuit between passenger's multiplex control unit and shift lock relay, and A/T gear position switch.
4. Turn ignition off. Disconnect shift lock solenoid harness connector. Check for continuity between passenger's multiplex control unit harness connector terminal No. 15 (Green/Yellow wire) and shift lock solenoid harness connector terminal No. 2 (Green/Yellow wire). If continuity exists, go to next step. If continuity does not exist, repair open in Green/Yellow wire between multiplex control unit and shift lock solenoid.
5. Connect battery voltage to shift lock solenoid connector terminal No. 1 (Yellow/Red wire), and connect ground to shift lock solenoid connector terminal No. 2 (Green/Yellow wire). Shift lock solenoid should click. If shift lock solenoid operates properly, go to next step. If solenoid does not operate properly, replace shift lock solenoid. See «SHIFT LOCK SOLENOID»(ref-121437-S25061265162001082500000) under REMOVAL & INSTALLATION.
6. Check for loose passenger's multiplex control unit harness connectors. Repair as necessary. If connectors are okay, substitute a known-good passenger's multiplex control unit and retest.

COMPONENT TESTS

Except Acura 3.5RL, & Honda Accord, Odyssey & Prelude

1. Remove lower panel from instrument panel. Disconnect interlock control unit harness connector. Interlock control unit is located behind left side of dash, near steering column or instrument panel. Inspect terminals for poor connection, corrosion or bending. Repair as necessary.
2. Using DVOM, check for continuity or voltage between specified terminals. (Scheme 142)- (Scheme 144). See «WIRING DIAGRAMS»(ref-121437-S12285601742001082500000). Repair circuit as necessary and recheck system. If circuit is okay, go to next step.
3. Substitute with a known-good interlock control unit and recheck system. If problem no longer exists, replace original interlock control unit.

Scheme 142

Scheme 143

Scheme 144

Acura 3.5RL, & Honda Accord & Odyssey

Shift interlock system is controlled by driver's multiplex system and is located in driver's underdash fuse/relay box. For diagnosis, see appropriate test under SYSTEM TESTS.

Shift interlock system is controlled by passenger's multiplex system and is located behind right kick panel. For diagnosis, see appropriate test under SYSTEM TESTS.

Except Honda Accord & Odyssey

1. Remove lower cover and knee bolster from left side of dash for access to steering lock harness connector. Disconnect steering lock harness connector.
2. Using a DVOM, check for continuity between designated terminals with ignition lock assembly in ACC position. See appropriate KEY INTERLOCK SOLENOID CONTINUITY SPECIFICATIONS table.
3. If continuity is as specified, go to next step. If continuity is not as specified, replace ignition lock assembly. Key interlock solenoid cannot be serviced separately. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.
4. Connect battery voltage and ground to appropriate harness connector terminals to check key interlock solenoid activation. See appropriate KEY INTERLOCK SOLENOID ACTIVATION TEST table. For terminal wire color identification, see «WIRING DIAGRAMS»(ref-121437-S12285601742001082500000) . Ensure ignition key cannot be removed with battery voltage applied.
5. If ignition key cannot be removed, key interlock solenoid is okay. If ignition key can be removed, replace ignition lock assembly. Key interlock solenoid cannot be serviced separately. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.

Honda Accord & Odyssey

1. Remove left side lower dash cover. Disconnect 7-pin steering lock harness connector located on lower right of steering.
2. Connect a DVOM between steering lock harness connector terminals No. 5 (White/Red wire) and No. 7 (White/Yellow wire). Turn ignition key to ACC position. Push in on ignition key. Continuity should exist. Release ignition key. Continuity should not exist. If continuity is as specified, go to next step. If continuity is not as specified, replace ignition/steering lock assembly.
3. Apply battery voltage to steering lock harness connector terminal No. 7 (White/Yellow wire) and ground to terminal No. 3 (Black wire). If ignition key can be removed, key interlock solenoid is okay. If ignition key cannot be removed, replace steering lock assembly. Key interlock solenoid cannot be serviced separately. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT.

KEY INTERLOCK SOLENOID CONTINUITY SPECIFICATIONS (ACURA)

KEY INTERLOCK SOLENOID CONTINUITY SPECIFICATIONS (HONDA)

KEY INTERLOCK SOLENOID ACTIVATION TEST (ACURA)

KEY INTERLOCK SOLENOID ACTIVATION TEST (HONDA)

Acura Integra

1. Turn ignition off. Remove center console. Disconnect parking pin switch 3-pin harness connector located near shift lock solenoid harness connector.
2. Ensure shift lever is in "P" position. Connect DVOM to parking pin switch harness connector terminals No. 1 (Black/White Wire) and No. 3 (Black wire). Push shift lever button. Continuity should exist. Release shift lever button. Continuity should not exist. If continuity is not as specified, replace parking pin switch.See «PARKING PIN SWITCH»(ref-121437-S24411774922001083000000) under REMOVAL & INSTALLATION.

1. Turn ignition off. Remove center console. Disconnect parking pin switch 2-pin harness connector located near shift lock solenoid harness connector.
2. Ensure shift lever is in "P" position. Check for continuity between parking pin switch 2-pin harness connector terminals. Push shift lever to the right. Continuity should exist. Release shift lever. Continuity should not exist. If continuity is not as specified, replace parking pin switch.See «PARKING PIN SWITCH»(ref-121437-S24411774922001083000000) under REMOVAL & INSTALLATION.

Honda Accord & Civic

1. Turn ignition off. Remove center console. Disconnect parking pin switch 4-pin harness connector located near shift lock solenoid harness connector.
2. Ensure shift lever is in "P" position. Check for continuity between parking pin switch harness connector terminals No. 3 (Black wire) and No. 4 (White/Black wire). Push shift lever button. Continuity should exist when shift lever button is pushed and not exist when released. If continuity is not as specified, replace park pin switch. See «SHIFT LEVER ASSEMBLY»(ref-121437-S27962228912001083000000) under REMOVAL & INSTALLATION.

1. Remove instrument panel lower cover. Remove upper and lower steering column covers. Disconnect park pin switch/overdrive switch 4-pin connector.
2. Ensure shift lever is in "P" position. Check for continuity between park pin switch/overdrive switch 4-pin harness connector terminals No. 3 (White/Black wire) and No. 4 (Black wire). Continuity should exist. Move shift lever from "P" position. Continuity should not exist. If continuity is not as specified, replace park pin switch. See «PARKING PIN SWITCH»(ref-121437-S24411774922001083000000) under REMOVAL & INSTALLATION.

1. Remove instrument lower cover. Remove upper and lower steering column covers. Disconnect park pin switch 3-pin connector.
2. Place shift lever in "P" position. Check for continuity between park pin switch 3-pin harness connector terminals No. 1 (Red wire) and No. 3 (Black wire). Continuity should exist. Move shift lever from "P" position. Continuity should not exist. If continuity is not as specified, replace control bracket assembly. See «SHIFT LOCK SOLENOID»(ref-121437-S25061265162001082500000) under REMOVAL & INSTALLATION.

1. Turn ignition off. Remove center console. Disconnect mode switch 8-pin harness connector.
2. Ensure shift lever is in "P" position. Check for continuity between mode switch harness connector terminals No. 3 (Black/White wire) and No. 8 (White/Black wire). Continuity should exist. Move shift lever from "P" position. Continuity should not exist. If continuity is not as specified, replace A/T gear position/mode/pin switch assembly. See «PARKING PIN SWITCH»(ref-121437-S24411774922001083000000) under REMOVAL & INSTALLATION.

Acura & Honda

1. Access shift lock solenoid. See «SHIFT LOCK SOLENOID»(ref-121437-S25061265162001082500000) under REMOVAL & INSTALLATION. Disconnect shift lock solenoid harness connector. Note connector terminals and wire colors. (Scheme 145) Also see «WIRING DIAGRAMS»(ref-121437-S12285601742001082500000).
2. Connect battery voltage to shift lock solenoid terminal No. 1 and momentarily connect solenoid terminal No. 2 to ground. On models equipped with floor mounted shift lever, ensure shift lock releases when release lever is pushed and locks when release lever is released. On models equipped with column mounted shift lever, ensure shift lever can be moved from "P" position when battery voltage is applied to shift lock solenoid and locks in "P" position when voltage is removed. Replace shift lock solenoid if solenoid does not operate properly.

Scheme 145