P28DA code meaning
Clutch B Motor Position Sensor Circuit/Open
Powertrain system Generic code P28xx codes Check engine light
What P28DA means
P28DA concerns the electrical circuit of the sensor that reports the rotor angle of the clutch B motor, and is chiefly stored when that signal disappears because a line is open. Electronic commutation of a brushless motor relies on this angle to energise U, V and W in the right order; it also lets the controller count revolutions and compare pump speed with the pressure sensor. Without a valid signal the clutch B pump is stopped and the gears on that shaft are no longer offered. Usual culprits are a broken sensor supply or ground, a pin pushed out of the connector, or a dead Hall or magnetic element inside the actuator. P28DB handles a signal that exists but is inconsistent; P28CB is the clutch A equivalent. Details are unpublished.
P28DA 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 P28DA
- Clutch B out of service, half of the gears missing
- Transmission warning lamp on
- Motor speed codes for clutch B may be stored as follow-up faults
Common causes of P28DA
- Most likelyOpen supply, ground or signal line of the clutch B motor position sensor
- PossiblePin pushed out or bent at the clutch B actuator connector
- PossibleFailed sensing element inside the clutch B actuator
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Clutch motor position sensor bWiring harnessTCM
What each part of P28DA 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. |
| DA | The exact fault in that area. |
What to do next
- Note P28DA 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 P28DA
What does P28DA mean?
P28DA means "Clutch B Motor Position Sensor Circuit/Open". P28DA concerns the electrical circuit of the sensor that reports the rotor angle of the clutch B motor, and is chiefly stored when that signal disappears because a line is open. It is a generic code, so it means the same on every make.
Is it safe to drive with P28DA?
Drive gently and only to a workshop. With P28DA the car can go into limp mode (reduced power) to protect itself.
Will P28DA fail an emissions test?
Yes, it can. P28DA 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 P28DA to fix?
Difficulty: hard. A typical repair takes 0.5 to 3.5 hours of work. This is a job for a workshop.
Will P28DA clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.