Powertrain, generic

P0E59 DC/DC Converter Temperature Sensor C Circuit Range/Performance

Check engine lightOn

EmissionsRelevant

Drive cycleRequired

Limp modePossible

P0E59 is the best-documented member of this group. Ford's hybrid OBD summaries from 2015 to 2019 assign it to the inductor temperature sensor of the variable voltage converter and monitor it without pause once 500 ms have passed since power-up, provided the 12 V supply lies between 6 and 19 V. It fails on any of three conditions: a sensor voltage under 0.067 V or over 4.86 V, an inductor reading above 165 °C for 1 s, or a value more than 30 °C away from engine coolant temperature after a soak of 180 minutes. Ford thus folds the electrical range checks into this code instead of using P0E5A/P0E5B. FCA also uses P0E59 on the 2021 Ram 1500 eTorque; bulletin 08-037-21 makes it a one-trip code with new HCP software. Sensors A and B have P0C39 and P0C3E as their plausibility codes.

Likely causes

Inductor temperature sensor drifting, reading off after cold soak

Inductor really overheating, e.g. due to weak electronics cooling

Hybrid control software (FCA HCP update)

Short or open in the sensor circuit (Ford range limits)

Symptoms

MIL on, at FCA after one faulty drive
Reduced hybrid assist or electric driving
Hybrid system warning

Repair estimate

DifficultyShop_onlyWorkshop job

Parts and labour€60–2,500

Time0.3–5 h

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

Parts involved

dcdc converter temp sensor cwiring harnessdcdc converter

References: fordservicecontent.com, fordservicecontent.com, static.nhtsa.gov.