Powertrain, generic (extended)

P2B9C Coolant Pump A Stuck/Stalled

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P2B9C signals that coolant pump A is powered and commanded but its rotor does not turn, or stops. Ford uses the code in its 2024 gasoline OBD summary as fault type 71 (actuator stuck) under P2600, where pump A is the auxiliary pump in the high-temperature loop for cabin heating; the check runs continuously above 11 V battery voltage over 5 seconds. Brushless pumps detect a locked rotor themselves, typically from high current without rotation, and report it to the engine computer; the GM patent US20160047374A1 explains how comparing measured current and speed with expected values exposes such faults. Usual reasons are a seized bearing, sludge or debris, frozen coolant or a burnt winding. Pump B has P2B63, pump D P2B6A. A pump that only runs slow sets P2B87.

Likely causes

Seized bearing or rotor in the auxiliary pump
Sludge, sealant residue or debris jamming the impeller
Coolant frozen in the pump due to weak antifreeze
Burnt motor winding or failed drive electronics

Symptoms

  • Little or no cabin heat
  • Check engine light
  • Pump silent when it should run

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€150–700
Time1–3 h

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

Parts involved

coolant pump awiring harnessecm

Related codes

P2B9DP2B9EP2B87P2B63P2B6AP26F8

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