Powertrain, generic (extended)

P26CF Engine Coolant Pump Control Module System Voltage

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

Smart coolant pumps carry their own electronics, which measure the supply voltage they receive. P26CF is the general code for that voltage when it is implausible but cannot be assigned to too low or too high. No manufacturer documents P26CF itself in public. Ford's hybrid OBD summaries show the principle with the sister codes P26D0 and P26D1: the pump module sends its electronics voltage over LIN, and the PCM compares it with its own battery reading. CARB requires electronic components that affect emissions to be checked for plausibility. A general system voltage fault usually points to a shared cause – loose grounds, a weak battery, charging problems or intermittent contact – rather than to the pump. The pump may reduce its output or stop.

Likely causes

Loose, corroded or intermittent pump supply or ground connection
Weak battery or charging system fault
Faulty voltage measurement in the pump electronics

Symptoms

  • Check engine lamp on
  • Other voltage-related codes stored at the same time

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€30–1,000
Time0.5–3 h

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

Parts involved

smart coolant pump modulecharging system

Related codes

P26D0P26D1P26D3P0562P0563

References: law.cornell.edu, fordservicecontent.com.