Glow Plug Control Module: Description and Operation

PURPOSE
Glow plug pre-glow and after-glow time and operation of the "Wait To Start" lamp are determined by a solid state controller.

OPERATION
The solid state glow plug controller determines the glow plug temperature by electronically measuring the resistance of the glow plugs, then maintains this temperature regardless of ambient temperature.

To reduce white smoke emissions during engine warm up, the controller cycles the glow plugs ON and OFF until the engine has reached normal operating temperature.

A "Wait To Start" lamp on the instrument panel is illuminated during glow plug heating. This lamp goes out when the glow plugs have reached the proper temperature.

CONSTRUCTION
The controller incorporates all glow plug control functions into one module. It consists of a power relay mounted on a circuit board. The relay and circuit board are covered with a protective plastic cover.