Powertrain, generic · Vehicle speed, idle control and auxiliary inputs
P052F Glow Plug Control Module 1 System Voltage
Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo
Diesel glow plugs are switched by a separate glow plug control module fed from the battery, with its own ground, a command from the engine module and a diagnostic line back. P052F means its supply voltage is out of range. Ford's 6.7 L and 3.0 L Power Stroke set it below 6.5 V, above 16.5 V or with an open supply, after about 1 s, continuously. An FCA bulletin shows P052F together with all six glow plug open codes P0671–P0676, because without supply no current flows – check main feed, connector and grounds first. GM does not use it.
Likely causes
Main feed to the module open or high-resistance (fuse, connector, corroded ring terminal)
Poor ground of the glow plug module
System voltage too low or too high (weak battery, regulator fault)
Glow plug module faulty internally
Symptoms
- Check engine light on
- Hard cold start, long cranking, white smoke
- Several glow plug codes at once
Repair estimate
DifficultyMediumDIY possible
Parts and labour€20–600
Time0.5–2.5 h
Typical range across vehicles; the real cost depends on what the testing finds.
Parts involved
glow plug control modulemodule power supplymodule groundengine control module
Related codes
References: fordservicecontent.com, static.nhtsa.gov, static.nhtsa.gov, saabwisonline.com.