Common Symptoms
- Glow plug indicator lamp remains on continuously after engine start
- Glow plug warning light does not illuminate at all during key-on
- Hard starting or extended cranking in cold weather
- White or gray smoke on cold start
- Rough idle immediately after cold start
- Engine hesitation or stumbling during cold start warm-up
Most Likely Root Causes
- Failed glow plug indicator lamp bulb or LED in instrument cluster
- Open or short circuit in glow plug indicator lamp wiring
- Faulty glow plug control module or relay
- Corroded or damaged connector at instrument cluster
- Failed instrument cluster circuit board
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Component Location
The glow plug indicator circuit runs from the glow plug control module through the instrument cluster to the warning lamp on the dashboard.
Manufacturer Notes
This code specifically monitors the indicator lamp circuit function and does not indicate actual glow plug heater element failure.
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