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Ignition System Diagnostics

  1. Locate the diagnostic unit and remove its cover. Connect selector cable to No. 6 socket. Turn ignition to "ON" position. Enter control function No. 1 (access codes) by pressing push button one time for at least one second and no more than 3 seconds. To enter control function No. 2, press push button twice for at least one second and no more than 3 seconds. To enter control function No. 3, press push button three times for at least one second and no more than 3 seconds.
  2. Watch the Red LED and count the number of flashes in the three-flash series. The flash series are separated by a three-second interval. See Figure . Note all codes. Only three separate codes can be stored at once. If no codes are stored, the LED will flash a 1-1-1 to indicate the ignition system is operating properly.
  3. If a fault code is received, refer to the IGNITION SYSTEM FAULT CODES  table. Depress push button again and check for additional codes. Depress push button a third time, if necessary. If the first code repeats, there are no other codes.
  4. The diagnostic system memory is full when three codes are present. Those three codes must be repaired before further codes can be retrieved.
IGNITION SYSTEM FAULT CODES

Code Fault Repair
1-1-1 No Faults N/A
1-4-2 ECU Replace ECU
1-4-3 Knock Sensor Signal (1)
1-4-4 Fuel System Load Signal (1)
2-1-4 Perm./Magnet Generator (1)
2-2-4 Coolant Temp. Sensor, Check Temp. Sensor (2)
2-3-4 Throttle Switch Signal (1)
(1) See IGNITION SYSTEM FAULT CODE TESTING  in this article.
(2) See SYSTEM/COMPONENT TESTS article in this section.