Glow Plug Controller

Fig 1: Glow Plug System Diagnosis (C/K, R/V, G, P)

A faulty controller may result in excessive White smoke and/or poor idle quality immediately after starting. The following procedure checks for proper operation of controller circuit. Ensure coolant temperature is below 80°F (27°C) before beginning test.

1. Place ignition switch in "RUN" position and allow glow plugs to cycle. After 2 minutes crank engine for one second. Return switch to "RUN" position. Glow plugs should cycle on at least once.
2. If glow plugs do not cycle, disconnect controller connector. Connect 12-volt test light between terminal "B" (Purple wire) of harness connector and ground. With ignition switch in "RUN" position, test light should be off. Test light should glow when engine is cranked.
3. If test light does not operate as specified, repair short or open in engine harness Purple wire. If test light operates properly but glow plugs did not cycle, replace controller.