Diesel Data: Automotive Repair

DR-5A Fault Code 18-V.O.S Control Solenoid Circuit


1. Connect diagnostic read-out tool to engine harness connector.
2. Open carburetor switch, turn ignition switch in Run position and place Read/Hold switch in hold position.
3. Display Code 55 on read-out tool.
4. Connect a voltmeter between black wire of the carburetor 6-way connector and ground.
5. Put system in ATM Test Mode 98.
6. If voltmeter is pulsating and reads between zero and 1 volt, proceed to Step D.
7. If voltmeter is not pulsating and reads within 1 volt of battery voltage, proceed to Step B.
8. If voltmeter is not pulsating and reads zero to 1 volt, proceed to Step C.