Powertrain, generic · Hybrid propulsion

P0CF1 Hybrid/EV Electronics Coolant Temperature Sensor A Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

The sensor signal rises nearly to the 5 V reference, the typical picture of an open circuit, an unplugged connector or a signal wire shorted to voltage. GM sets it above 98 % of the reference (4.9 V) in all published tables from the 2011 Volt to the 2019 HPC2 controller, 16 of 20 samples at 250 ms or 4 s within 5 s, Type B, two trips. Chrysler's Pacifica Hybrid shows it in practice: STAR case S2008000119 (2020, revised 2021) links P0CF1 together with P1B71-00 and B12B0-00 and the message Service Hybrid Electrical System to water entering the grey 16-pin inline connector XY291A under the battery skid plate. Cleaning and dielectric grease cure light moisture; corroded pins mean new dash and underbody harnesses. P0CF0 is the grounded counterpart.

Likely causes

Water or corrosion in an underbody inline connector (Chrysler Pacifica Hybrid XY291A)
Open signal or ground wire, or unplugged sensor
Sensor element open internally
Signal wire shorted to a voltage source

Symptoms

  • Service Hybrid Electrical System or similar warning
  • Scan tool shows an implausibly low coolant temperature
  • Charging or drive power limited

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€30–900
Time0.5–4 h

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

Parts involved

hybrid electronics coolant temp sensor awiring harnesshybrid control module

Related codes

P0CEEP0CEFP0CF0P0CF2P2B23

References: gsi.ext.gm.com, gsi.ext.gm.com, static.nhtsa.gov, static.nhtsa.gov.