Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Glow Plug Controller
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.
- 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.
- 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.
- 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.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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