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Corolla, Pickup, 4Runner, Celica Supra, Van

  1. Turn ignition on. If ECU-IC or gauge fuse is normal, go to step 2) or 5). If not, replace fuse. If operation is still not normal, check for short in harness between fuse and terminal 1 (Van) or 3 (all others) of the main switch.
  2. For RWD Corollas, use this step and steps 3) and 4). For all others, go to step 5). Check control switch power source by checking for 12 volts between terminal 3 of main control switch and ground. If none, there is open in harness between fuse and terminal 3.
  3. If there is continuity, inspect ground connection by disconnecting switch and checking for continuity between terminal 4 of harness side and ground. If no continuity, the body ground is bad or there is open in harness between terminal 4 and ground.
  4. If continuity existed in step 3), turn main switch on and check operation by testing for 12 volts between terminal 7 and ground. If none, inspect main switch. If continuity, go to step 9).
  5. Check main switch power source. There should be 12 volts between terminal 1 (Van, Celica and Supra) or 3 (Pickup, 4Runner and Cressida) and ground. If not, check for open in harness between fuse and terminal.
  6. If 12 volts were present, inspect ground connection by disconnecting connector from main switch. There should be continuity between terminal 5 (Celica and Supra) or 4 (all others) of harness connector side and ground. If not, the ground is faulty or there is an open in harness between terminal 4 or 5 (as applicable) and ground.
  7. If 12 volts were present in step 6), inspect switch operation. With main switch turned on, check for 12 volts between terminal 2 (Van and Cressida), 3 (Celica and Supra) or 7 (Pickup, 4Runner) and ground. If none, inspect main switch.
  8. If 12 volts were present in step 7), inspect control switch ground connection. Disconnect connector from control switch and check for continuity between terminal 9 (Van) or 14 (all others) of harness connector side and ground. If no continuity, check for open in harness between terminal 9 or 14 (as applicable) and ground.
  9. If continuity existed in step 8) or 4), inspect "SET/COAST" switch operation. Turn switch on and check for continuity between terminal 1 (Van), 5 (Corolla RWD), 24 (Pickup, 4Runner, Supra and Cressida) or 25 (Celica and Corolla FWD) and ground. If none exists, inspect control switch.
  10. If continuity existed in step 9), turn "SET/COAST" switch off and check that there is no continuity between terminal 1 (Van) and ground. If none, inspect control switch. For Celica, Supra, Pickup, 4Runner and Corolla, turn "SET/COAST" switch off and check for continuity between terminal 25 (Celica), 5 (Corolla RWD), 30 (Supra) or 24 (Pickup, 4Runner, Cressida and Corolla FWD) and ground. If there is continuity, inspect control switch.
  11. Inspect "ACCEL/RESUME" switch. For Van, if continuity existed in step 10), turn "ACCEL/RESUME" switch on and check for continuity between terminal 2 and body ground. If none, inspect control switch. For others, if no continuity existed in step 10), turn "ACCEL/RESUME" switch on and check for continuity between terminal 28 (Supra), 2 (Corolla RWD), or 23 (Celica, Cressida,Corolla FWD and Pickup, 4Runner) and ground. If none exists, check control switch. For all but Van, go to step 15).
  12. For Vans, check the brake cancel switch. If continuity existed in step 11), be certain brake pedal is not depressed and check for continuity between terminal 2 of brake cancel switch and ground. If there is continuity, there is a severed wire between brake cancel switch terminal 1 and actuator terminal 5. Check actuator.
  13. For Vans, if no continuity existed in step 12), disconnect actuator and brake cancel switch connector. Check for continuity between brake cancel switch terminal 1 and ground. If yes, there is short in harness between brake cancel switch terminal 1 and actuator terminal 5.
  14. For Vans, check stop light switch. If no continuity existed between brake cancel switch terminal 1 and ground, check for continuity between terminal 1 and 2 with the brake pedal depressed. If none, inspect stop light switch. If there is continuity, disconnect stop light switch and computer connector. If there is no continuity, there is an open in harness between terminal 12 of computer and terminal 1 of stop light switch. If there is continuity, go to step 1) under COMPUTER TEST.
  15. For others, check stop light switch by inspecting release valve circuit. Continuity must have existed in step 11) while checking terminals 2, 28 or 23 (as applicable). Release valve circuit resistance value for Celica, Cressida, Corolla and Supra should be about 30 ohms between terminal 1 and 2 of computer with the brake pedal returned. For Pickup & 4Runners it should be about 71 ohms between terminal 1 and ground with brake pedal returned.
  16. If there is no continuity, check for open or short in harness between terminal 2 (Pickup & 4Runner) or 4 (Corolla RWD, Cressida, Celica and Supra) of stop light switch and terminal 3 of actuator. Also check for open in harness between terminal 1 of actuator and terminal 17 (Pickup & 4Runner) or 2 (Celica, Cressida, Corolla and Supra) of computer. Inspect stop light switch and actuator also.
  17. If there was correct reading in step 15), inspect stop light switch operation by depressing brake pedal and checking for continuity between terminal 3 and 4 (Pickup & 4Runner) or 1 and 2 (Celica, Cressida, Corolla and Supra). If no continuity, inspect stop light switch.
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