P277D code meaning
Electric/Auxiliary Transmission Fluid Pump B Motor Over Temperature
What P277D means
P277D reports that the motor or the integrated electronics of auxiliary pump B have become too hot. Pumps of this kind measure their own temperature and stop before damage occurs; the code records that protective shutdown. Heat builds up when the pump runs long at high load, for example many stop-start phases in hot traffic, when it drags mechanically, when the fluid is overheated or degraded, or when its cooling path is blocked. No manufacturer documents P277D publicly. For pump A, Ford's 2024 summary of the 10R60/10R80 and 8F57 gearboxes has the counterpart: an over-temperature message from the pump becomes P175A, in UDS form P0C29_4B; P0DE4 is the generic pump A code. Once the pump has cooled it may work again, so a recurring code calls for checking current draw and fluid condition.
P277D at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyHard
- Typical labor0.5 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P277D
- Stop-start temporarily unavailable, especially in hot weather
- Warning lamp or transmission message
Common causes of P277D
- Most likelyLong high-load operation in hot conditions
- PossibleMechanical drag raising motor current and heat
- PossibleOverheated or aged transmission fluid
- Less likelyFaulty temperature sensing in the pump electronics
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Aux trans pump bPump motor
What each part of P277D means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 7 | Area: transmission. |
| 7D | The exact fault in that area. |
What to do next
- Note P277D and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P277D
What does P277D mean?
P277D means "Electric/Auxiliary Transmission Fluid Pump B Motor Over Temperature". P277D reports that the motor or the integrated electronics of auxiliary pump B have become too hot. It is a generic code, so it means the same on every make.
Is it safe to drive with P277D?
P277D does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will P277D fail an emissions test?
P277D is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P277D to fix?
Difficulty: hard. A typical repair takes 0.5 to 4 hours of work. This is a job for a workshop.
Will P277D clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.