Code 18
- Connect diagnostic read-out box to the engine harness connector. Place carburetor switch in "OPEN" position. Turn ignition switch to the "RUN" position. Place Read/Hold switch in the "Hold" position. Code 55 should appear on display of read-out box.
- Connect voltmeter to the Black wire of the carburetor 6-pin connector and ground. Press and hold the ATM button until test code 98 appears on the display. Voltmeter should be pulsating and the solenoid clicking. If voltmeter is not pulsating but reads within one volt of battery voltage, proceed to step 4).
- If voltmeter is not pulsating but reads 0-1 volt, turn ignition switch to "OFF" position. Disconnect the computer 14-pin connector. Turn ignition switch to "RUN" position. If voltage is now within one volt of battery voltage, replace computer. If still 0-1 volt, repair V.O.S control solenoid wire for a short to ground. If voltmeter pulsates between 0-1 volt proceed to step 5).
- Turn the ignition off. Disconnect computer 14-pin connector. Connect voltmeter to the 14-pin connector cavity No. 8 and ground. Turn the ignition switch to the "RUN" position. If voltmeter reads within one volt of battery voltage, check terminal in connector cavity No. 8 to ensure it is not spread apart causing a poor connection. If connection is okay, replace the computer. If voltage is not okay, repair wire of cavity No. 8 for an open circuit to the V.O.S. control solenoid.
- With carburetor 6-pin connector disconnected, connect a voltmeter to the Blue wire of the harness 6-pin connector and ground. Turn the ignition switch to the "RUN" position. If voltmeter reads within one volt of battery voltage, replace the V.O.S. control solenoid. If zero volts, repair the Blue wire for an open circuit to the ignition switch.