Glow Plug: Description and Operation

PLUG-GLOW

DESCRIPTION






CAUTION:
- The glow plug system is a 7 volt system. The glow plugs DO NOT tolerate any over voltage. Full battery voltage will destroy the glow plug immediately. DO NOT test the glow plugs with a 12V source as damage will occur to the glow plug.

- Never bend, bump or knock the ceramic glow plugs.
- Ceramic glow plugs must not be handled loose in a container. Store, handle, and transport them only in original boxes.
- If there is any doubt about the proper condition of a glow plug, do not use it anymore.
- Do not clean the glow plugs with abrasive or aggressive media.
- Avoid dipping the glow plug into fluids.
- Read Diagnostic Trouble Codes (DTCs). If a glow plug problem is indicated, do not start the engine.

- Disregarding these instructions may cause severe engine damage.

Glow plugs are used to help start a cold or cool engine. The glow plugs will heat up and glow to heat the combustion chamber of each cylinder. An individual glow plug is used for each cylinder. Each glow plug is threaded into the left side of the cylinder head below the cylinder head cover/intake manifold.

OPERATION






CAUTION: The glow plug system is a 7 volt system. DO NOT test the glow plugs with a 12 V source as damage will occur to the glow plug(s).

The Engine Control Module (ECM) monitors various engine sensors. When the ignition key is turned to the ON position, the ECM sends a signal to the glow plug module to turn on, and cycle, the glow plugs for a predetermined amount of time, plus illuminate the glow plug light in the instrument panel. Once activated, the element inside of the ceramic core of the glow plug begins to glow. Each glow plug draws approximately 5 amps, for a total system amperage of 20 amps at 22° C (72° F) ambient temperature. If there is a fault with the glow plug system, the ECM will store a fault code.