P28D2 code meaning
Clutch B Motor Phase U-V-W Circuit Low
Powertrain system Generic code P28xx codes Check engine light
What P28D2 means
P28D2 reports that on the U, V or W lead feeding the electric drive of clutch B a voltage below its expected level is measured, pointing to a short towards ground. Such motor-driven clutches are found in wet dual-clutch units of the Getrag/Magna pump-actuator family; the 7DCT300 went into series in 2015 with the Renault Espace, and the hybrid 7HDT300 uses the same principle. In the Stellantis hybrid version clutch B carries the even gears. Frequent triggers are insulation rubbed through on a bracket, water in the actuator plug or a failed low-side transistor. Overvoltage on a phase is P28D3, an open lead P28D4; P28C4 is the clutch A twin. No carmaker publishes a limit; the even-shaft gears may be withheld.
P28D2 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor0.5 to 3.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P28D2
- Transmission warning light, MIL possible
- Gears on the clutch B shaft unavailable (even gears on the 7HDT300)
- Harsh or hesitant gear changes
Common causes of P28D2
- Most likelyInsulation of a clutch B motor phase rubbed through against ground
- PossibleWater or corrosion in the clutch B actuator plug pulling a phase low
- Less likelyFailed low-side transistor of the clutch B motor driver
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Clutch motor bWiring harnessTCM
What each part of P28D2 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. |
| D2 | The exact fault in that area. |
What to do next
- Note P28D2 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 P28D2
What does P28D2 mean?
P28D2 means "Clutch B Motor Phase U-V-W Circuit Low". P28D2 reports that on the U, V or W lead feeding the electric drive of clutch B a voltage below its expected level is measured, pointing to a short towards ground. It is a generic code, so it means the same on every make.
Is it safe to drive with P28D2?
Drive gently and only to a workshop. With P28D2 the car can go into limp mode (reduced power) to protect itself.
Will P28D2 fail an emissions test?
Yes, it can. P28D2 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 P28D2 to fix?
Difficulty: hard. A typical repair takes 0.5 to 3.5 hours of work. This is a job for a workshop.
Will P28D2 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.