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Shift Interlock System

  1. To check system operation, ensure shift lever is in Park. Turn ignition on. Depress brake pedal with accelerator pedal in idle position.
  2. If shift lock solenoid clicks, system is working properly. If shift lock solenoid fails to click, go to step 3). If shift lever cannot be moved from Park, check for proper installation procedure of shift lock solenoid. See SHIFT LOCK SOLENOIDS  under REMOVAL & INSTALLATION. If shift lock solenoid installation is okay, check shift cable and shift components at transaxle.
  3. Disconnect 8-pin electrical connector from interlock control unit. Interlock control unit is located above driver's side kick panel and contains a MD7Gray 8-pin electrical connector. Refer to the Figs. Figure -Figure .
  4. Turn ignition on and depress brake pedal. Using voltmeter, check voltage at White/Green  wire of 8-pin electrical connector and ground. Battery voltage should exist.
  5. With brake pedal still depressed, depress accelerator pedal. Ensure brake pedal and accelerator are held down at the same time. Check voltage at White/Green  wire of 8-pin electrical connector and ground. Battery voltage should not exist.
  6. If voltage readings in steps 4) and 5) are as specified, go to step 8). If voltage is not as specified in steps 4) and 5), check No. 41 fuse (15-amp) in engine compartment fuse box. Engine compartment fuse box is located on passenger's side rear corner of engine compartment, near firewall. If fuse is okay, check for defective wiring.
  7. If wiring checks okay, check for a defective brakelight switch or throttle position sensor. Refer to BRAKELIGHT SWITCH  and THROTTLE POSITION SENSOR  under COMPONENT TESTING. If all components are okay, substitute TCM and recheck operation.
  8. Ensure shift lever is in Park. Using ohmmeter, check continuity between Green  /White wire of 8-pin electrical connector and ground. Continuity should exist. If continuity exists, go to step 10).
  9. If continuity does not exist, check the A/T gear position switch. See A/T GEAR POSITION SWITCH  under COMPONENT TESTING. If the A/T gear position switch is okay, check for defective wiring or ground connections G401, G402, G404 and G521 (1994 models). See Figure and refer to the GROUND CONNECTION LOCATIONS  table.
  10. Ensure ignition is on. Using voltmeter, check voltage at Green  wire of 8-pin electrical connector and ground. If battery voltage exists, wiring circuit is okay.
  11. If battery voltage does not exist, check for defective No. 13 fuse (10-amp), located in fuse/relay box behind driver's side kick panel. If fuse is okay, check for defective wiring circuit. If wiring circuit checks okay, check the shift lock solenoid. Refer to SHIFT LOCK SOLENOID  under COMPONENT TESTING.
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