Powertrain, generic

P0E14 Hybrid/EV Battery Pack Coolant Heater A Control Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0E14 is logged when heater A's control wire sits too high, typically because it touches a supply voltage or because a pulled-up input has lost its connection. No manufacturer documents P0E14 publicly; GM's 2016 Volt reports open, ground and voltage faults of its heater transistor together as P1EC3 (Type B). The high case deserves care because, depending on the design, a line held at supply voltage can keep the heater energised against the controller's will. Heater makers guard against that: a patent now held by PTI EV Hybrid describes a battery coolant heater with a thermistor in its housing that cuts power when the coolant warms faster than a set rate. CARB requires circuit monitoring of battery heating outputs. P0E13 is the low counterpart, P0E12 the open circuit.

Likely causes

Command wire shorted to a supply or neighbouring live wire
Open connection on a pulled-up heater input reading as high
Output driver in the controller that will not switch off

Symptoms

  • Check engine light on
  • Heater shut down by its own overheat protection
  • Battery heating unavailable or erratic in cold weather

Repair estimate

DifficultyHardWorkshop job
Parts and labour€80–1,500
Time1–4 h

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

Parts involved

hv battery pack coolant heater awiring harnessbms

Related codes

P0E12P0E13P0E15P0E18P0C49

References: gsi.ext.gm.com, patents.google.com, law.cornell.edu.