P2B9DCoolant Pump A Supply Voltage Circuit
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P2B9D means the power feed of coolant pump A is outside its usable range, as opposed to the command line covered by P2600 to P2603. Ford names it in the 2024 gasoline OBD summary as fault type 1C (feed voltage outside its window) of the cabin-heating auxiliary pump, monitored all the time from 11 V battery voltage with a 5-second window. Since these pumps carry their own electronics, they measure the voltage on their supply pin and report the deviation. Look for a blown fuse, a relay with burnt contacts, corrosion in the plug, a bad ground strap or a weak battery; a voltage-drop test with the pump running finds hidden resistance best. CARB 13 CCR 1968.2 (e)(15) demands monitoring of such outputs. The same fault on pump B is P2B62, on pump D P2B69.
- What you may notice
- Cabin heat weak or missing
- Check engine light
- Fault comes and goes with battery condition or electrical load
- Likely causes
- LikelyBlown fuse or faulty relay in the pump supply
- PossibleCorroded connector or poor ground at the pump
- PossibleWeak battery or charging system voltage too low
- RareChafed or broken supply wire
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €10 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.