P28D7 code meaning
Clutch B Pump Motor Performance
Powertrain system Generic code P28xx codes Check engine light
What P28D7 means
P28D7 judges motor and pump of clutch B as one unit: the oil pressure seen by the sensor, or the speed and current the motor needs for it, does not match the target. Getrag's hydraulic plan for the 7DCT300 has both clutch pumps drawing through a common suction filter, with a pressure sensor downstream of both pumps providing feedback. If P28D7 and the clutch A code P28C8 are stored together, the shared filter or the oil level is therefore a natural suspect; P28D7 on its own points more towards the clutch B pump, its gerotor set or leaking seals in the clutch B circuit. An EVS32 study with Hyundai found such on-demand pumps cut actuation energy by 96.5 % in the WLTP versus an engine-driven pump. No manufacturer documents P28D7 publicly.
P28D7 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor1 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P28D7
- Clutch B slips or engages late
- Transmission warning, gears on clutch B possibly locked out
- Unusual humming from the actuator area
Common causes of P28D7
- Most likelyClogged common suction filter, especially if P28C8 is stored too
- PossibleLeaking seals in the clutch B pressure circuit
- PossibleWorn or contaminated gerotor set of the clutch B pump
- Less likelyTransmission fluid level too low
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Clutch motor bClutch actuator b
What each part of P28D7 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 8 | Area: transmission. |
| D7 | The exact fault in that area. |
What to do next
- Note P28D7 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 P28D7
What does P28D7 mean?
P28D7 means "Clutch B Pump Motor Performance". P28D7 judges motor and pump of clutch B as one unit: the oil pressure seen by the sensor, or the speed and current the motor needs for it, does not match the target. It is a generic code, so it means the same on every make.
Is it safe to drive with P28D7?
Drive gently and only to a workshop. With P28D7 the car can go into limp mode (reduced power) to protect itself.
Will P28D7 fail an emissions test?
Yes, it can. P28D7 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P28D7 to fix?
Difficulty: hard. A typical repair takes 1 to 4 hours of work. This is a job for a workshop.
Will P28D7 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.