Glow Plug System
Current to glow plugs flows through starter relay to Preheat Control Box (located at center of firewall). A timer in control box provides power to glow plug, depending on ambient temperature, for 0-30 seconds. The following check can be made on this system:
- Check system ground between terminal 2 on control box and frame. Check condition of glow plug bulb and ground connection in instrument panel.
- To locate shorted glow plugs, remove connecting straps between plugs. Connect a heavy jumper wire between terminal 5 of control box and each plug, 1 at a time.
- Leave jumper wire connected for about 2 seconds. If glow plugs are bad, glow plug relay will cycle rapidly on and off. Replace shorted glow plugs.