Powertrain, generic · Auxiliary emission controls

P041D EGR Temperature Sensor B Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

EGR temperature sensor B measures the gas temperature in the EGR path – for cooler monitoring, component protection and the EGR model. Whether it sits before or after the cooler depends on the maker: GM diesels have sensor A after and B before the cooler, Ford diesels sensor B after it. Like a coolant sensor it is an NTC, so a low voltage means hot. P041D means the signal is above its upper limit – very cold or, far more often, an open circuit; Ford puts above 4.90 V at about −46 °C. Thresholds: Ford diesel above 4.90 V, Ford petrol above 4.94 V for 5 s, GM's Duramax LML above 4.84 V, GM 2018 a resistance above 859 Ω; MIL after two trips. A substitute value is used and the EGR cooler check is suspended.

Likely causes

Connector off or broken wire
Sensor open internally
Ground open or short to positive
Engine module

Symptoms

  • Check engine light on
  • Usually no change in driving
  • Substitute value used, EGR cooler check suspended

Repair estimate

DifficultyEasyDIY possible
Parts and labour€50–250
Time0.5–1.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

egr temperature sensor begr coolersensor wiringengine control module

Related codes

P041AP041BP041CP041EP040D

References: fordservicecontent.com, fordservicecontent.com, gsi.ext.gm.com, gsi.ext.gm.com.