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Computer Test

  1. If there is continuity after step 11), check computer. Disconnect computer and inspect connector on harness side. Turn main switch on. 12 volts should exist between terminal 7 and ground. If not, check for open in harness between terminal 7 of computer and terminal 1 of main switch.
  2. If continuity existed in step 1) inspect ground connection. Continuity should exist between terminal 10 and ground. If not, check for open in harness between applicable terminal and ground.
  3. If continuity existed in step 2), inspect "SET/COAST" switch circuit. Turn "SET/COAST" switch on and check for continuity between terminal 4 and ground. If none, check for open between terminal 4 of computer and terminal 25 of control switch. Inspect control switch.
  4. If continuity existed in step 3), turn "SET/COAST" switch off and check for continuity between terminal 4 and ground. If continuity exists, check for short in harness between terminal 4 and terminal 24 of control switch. Inspect control switch.
  5. If no continuity existed in step 4), check "ACCEL/RESUME" switch circuit by turning switch on and checking for continuity between terminal 13 and ground. If no continuity exists, check for a short in harness between terminal 13 computer and terminal 23 and control switch. Inspect switch.
  6. There should be no continuity in step 5) with the "ACCEL/RESUME" switch off. If continuity, check for a short in harness between terminal 13 of computer and terminal 23 of control switch.
  7. Inspect control valve circuit. There should be a resistance value of about 68 ohms between terminals 2 and 3. If not, there is an open between terminal 3 of computer and 2 of actuator or an open in circuit in harness between terminal 1 of actuator and 2 of computer. Inspect actuator.
  8. If step 7) was okay, inspect release valve circuit for about 30 ohms between terminals 1 and 2 with the brake pedal returned. If not right, check for open or short in harness between terminal 1 of computer and 3 of actuator and between 1 of actuator and 2 of computer. Inspect stop light switch.
  9. If yes after the last 3 steps, use this step for manual transmission models or step 10) for automatic transmission models, as applicable. For manual transmission models, check for continuity between terminal 11 and body ground. Clutch pedal must be returned. If continuity exists, there is a short in harness between terminal 11 of computer and terminal 3.
  10. For automatic transmission, check for 12 volts between terminal 11 and body ground when shifting except to all but "N" position. If yes, there is a short in harness between terminal 11 of computer and terminal 3 of neutral start switch. Inspect switch.
  11. Inspect parking brake switch. 12 volts must not have existed in step 10), or no continuity must have existed in step 9). Return parking brake lever and check for 12 volts between terminal 12 and ground. If incorrect, there is short in harness between terminal 12 of computer and parking brake switch.
  12. If 12 volts existed between terminal 12 and ground in step 10), inspect speed sensor circuit. Disconnect connector from combination meter and check for continuity between terminal 23 of the harness side of connector and terminal 6 of computer. If no continuity exists, find open in circuit.
  13. If continuity exists in step 19), check for continuity between terminal 6 and ground. If yes, there is a short in harness between that terminal and terminal 23 of combination meter.
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