Powertrain, generic (extended)

P2D27 Coolant Pump F Control Circuit Performance/Stuck Off

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P2D27 is the functional check for coolant pump F, the sixth auxiliary pump in the lettering scheme and thus only relevant on vehicles with very many electric pumps, typically plug-in hybrids, electric vehicles or heavy diesels with several separate loops. The control line answers, yet the pump stays off or falls short of what the module expects from speed, current or temperature response. No manufacturer publicly documents P2D27, and unlike pump E no further pump F fault codes appear in common code lists. Published logic exists only for siblings: GM's 2025 diesel table judges pump C (P2C48) by comparing phase current with speed above 2,800 rpm, 10 failures out of 12, type B. Ford's 2024 gasoline summary watches its pumps A and B (P2601, P261B) for 5 s from 11 V. Check the loop, then pump and wiring.

Likely causes

Pump F blocked or worn so it runs too weakly
Air pocket or low coolant in the circuit of pump F
Corroded connector or high resistance in the pump F supply

Symptoms

  • Malfunction indicator lamp on
  • Overtemperature in the component or loop served by pump F
  • Power limitation if the cooled component protects itself

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–900
Time0.5–3 h

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

Parts involved

coolant pump fwiring harnessecm

Related codes

P2D26P2C48P2C49P2DF9P2601

References: law.cornell.edu, gsi.ext.gm.com, fordservicecontent.com.