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Glow Plug System

  1. Connect a 12 volt test lamp between the glow plug power relay output and ground. Turn ignition on. Test lamp should light, stay lit for 4 to 10 seconds, then cycle on and off. If so, proceed to step 2. If test lamp does not light, perform Glow Plug Test C. If test lamp stays on continuously, perform Glow Plug Test B. If test lamp lights for 4-10 seconds and then goes out, perform Glow Plug Test E.
  2. With test lamp still connected, start engine. Test lamp should cycle on and off for 20 to 90 seconds then turn off. If so, perform Glow Plug Test A. If test lamp continues to cycle on and off after 90 seconds, perform Glow Plug Test D. If test lamp does not light, perform Glow Plug Test E.
Fig 1: Engine Wiring System Diagram
G9748