Reading and Clearing Diagnostic Trouble Codes

WARNING: THIS TEST IS A KEY ON ENGINE OFF (KOEO) TEST ONLY THAT IS CONDUCTED IN PARK ONLY WITH THE PARKING BRAKE FULLY ENGAGED.

^ Enter Self-Test Diagnostics by depressing the speed control actuator switch OFF while turning the ignition switch to the RUN position, making sure the engine does not start and is not running. The speed control indicator in the instrument cluster will flash once to indicate that the speed control servo entered the diagnostic mode.

NOTE: Five additional flashes at this point indicate a defective speed control servo.

^ Release the OFF switch.
^ Depress the remaining speed control actuator switches in this sequence: ON, RESUME, COAST, and SET/ACCEL. The speed control indicator lamp will flash as each speed control actuator switch is depressed. Press each speed control actuator switch in the sequence immediately after the speed control indicator lamp goes out for the previous switch.

NOTE: If the speed control actuator switch ON is not pressed within five seconds after entering the diagnostic mode, the speed control servo times out and the procedure must be started over.

^ A speed control indicator lamp flash with the last button (SET/ACCEL) indicates that the STATIC test passed. If the speed control indicator lamp does not flash with the last speed control actuator switch and there are no additional flashes of the speed control indicator, the speed control actuator switch is defective. If the speed control indicator does not flash with the last speed control actuator switch, and additional flashes occur, follow the chart below for flash codes:
- 2 flashes - BPP switch is defective, circuit is defective, or brake pedal is applied.
- 3 flashes - Deactivator switch is open or circuit is defective.
^ Immediately after the static test has passed, the speed control servo will then carry out a dynamic test automatically by actuating the throttle lever from 1 mm to 10 mm of travel from the idle position. During the dynamic throttle pull, observe the throttle movement to witness any binding or sticking of speed control actuator cable, correct connection of the speed control actuator cable to throttle lever, and ensure throttle returns back to idle position. If incorrect connection and/or binding or sticking of speed control actuator cable is observed, REPAIR or INSTALL a new speed control actuator cable.
^ Return ignition switch to the OFF position and go to the Symptom Chart. Diagnosis By Symptom