Glow Plug Control Module

Drives each glow plug individually and monitors its current, which is what lets a modern diesel name the specific cylinder whose plug has failed. Also continues heating after the engine has started, to cut cold-running emissions and noise. Usually mounted low in the engine bay, so its connector suffers from water and salt — and several glow plug faults reported at once point here rather than at several failed plugs.

Also known as: glow plug relay, glow plug controller, gpcm, preheat module, glow control unit

Referenced by 78 codes

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Codes involving this component (78)

Other components in Engine Management and Sensors

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