P277CElectric/Auxiliary Transmission Fluid Pump B Motor Stalled
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Can trigger limp mode
- How the car detects it
- P277C means the motor of auxiliary pump B is commanded to turn but stands still or nearly so. Volvo uses it: its technical journal 36774 covers 2024–2027 mild-hybrid S60, S90, V60/V90 Cross Country, XC40, XC60 and XC90 models with the Aisin TG-81SC eight-speed, where the TCM stores P277C07. If the code shows up only intermittently, no warning appears and stop-start still works, Volvo says to clear it and not to replace anything. Confirmed with a warning and dead stop-start, gearboxes built before serial 25M8L30144 are replaced, while later units go to engineering support first. Ford's pump A equivalent is P0C2A, which its 2024 summary links to a pump that may have lost prime. A jammed impeller or seized bearing is the classic cause.
- What you may notice
- Transmission warning message in the cluster
- Stop-start not working
- Shifts too early, too late or erratic
- Likely causes
- LikelyJammed impeller or seized pump bearing
- PossibleKnown hardware issue in early gearboxes (Volvo TG-81SC before the serial break)
- PossiblePump lost prime because of low fluid
- RareOne-off detection without a real fault
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €0 – €6,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.