A shorted or low-resistance glow plug causing excessive current draw; Faulty glow plug control module 2 with an internal thermal fault; Damaged or corroded wiring between the module and glow plugs creating resistance; Poor electrical ground connection for the control module; Restricted airflow or debris blocking cooling of the module; A charging system fault causing low voltage and increased current draw; Aftermarket or incorrect glow plugs with wrong resistance specifications

DTC codes / P26xx · Computer and output circuits / P263F

P263FGlow Plug Control Module 2 Over Temperature

Q: What does code P263F mean?

Glow Plug Control Module 2 Over Temperature. P263F indicates that the glow plug control module 2 has reported an internal over-temperature condition to the engine control module. The module monitors its own temperature and sets this code when it exceeds a calibrated threshold, typically due to excessive current draw, poor cooling, or an internal fault.

P263F indicates that the glow plug control module 2 has reported an internal over-temperature condition to the engine control module. The module monitors its own temperature and sets this code when it exceeds a calibrated threshold, typically due to excessive current draw, poor cooling, or an internal fault.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaComputer and output circuits

Symptoms you may notice

Illumination of the check engine light or glow plug warning lamp
Hard starting or rough running when cold, especially in diesel engines
Extended cranking times before the engine fires
White smoke from the exhaust after a cold start
Reduced fuel economy during warm-up
Often no symptoms besides the warning light

Common causes, most likely first

A shorted or low-resistance glow plug causing excessive current draw
Faulty glow plug control module 2 with an internal thermal fault
Damaged or corroded wiring between the module and glow plugs creating resistance
Poor electrical ground connection for the control module
Restricted airflow or debris blocking cooling of the module
A charging system fault causing low voltage and increased current draw
Aftermarket or incorrect glow plugs with wrong resistance specifications

How to diagnose and fix it

Scan all modules for stored and pending codes, and record freeze-frame data for P263F
Inspect the glow plug control module 2 connectors and wiring for corrosion, chafing, or loose pins
Measure the resistance of each glow plug and compare to the manufacturer's specification
Check the module's ground circuit for excessive voltage drop under load
Verify charging system voltage and battery condition to rule out low-voltage-induced overcurrent
Test the control module's temperature sensor signal or substitute a known-good module if accessible
Replace the glow plug control module 2 and clear codes, then verify the repair with a cold-start test

Why glow plug modules overheat without warning

A single glow plug with resistance that has drifted low can draw enough extra current to overheat the module without ever setting a glow plug circuit code.
The module's over-temperature protection may derate or shut down glow plug operation entirely, so the driver notices cold-start problems rather than a module-specific fault.
Corroded ground connections are a frequent hidden cause because they raise resistance and force the module to work harder, yet they often pass a simple visual inspection.
Aftermarket glow plugs with incorrect resistance are a common misdiagnosis trap; always compare against the original equipment specification rather than a generic listing.
P263F can be set by a module that is actually healthy but mounted in a location with poor airflow or debris buildup, so check the mounting area before condemning the part.

Can I keep driving with P263F?

You can usually drive the vehicle, but cold starting may become difficult and repeated over-temperature events can damage the control module further. Avoid long cranking sessions and have the fault diagnosed soon, especially if the engine runs rough or produces smoke when cold.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.