Powertrain, generic (extended)

P28CD Clutch A Pressure Sensor Circuit/Open

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P28CD concerns the pressure sensor that tells the transmission controller how much oil pressure acts on clutch A. In pump-actuated wet DCTs there is no proportional valve to set pressure; instead Getrag places a pressure sensor downstream of the clutch pumps and closes the control loop over motor speed. P28CD is the general circuit fault, chiefly an interrupted signal, supply or ground line, so the controller receives no usable reading at all. Without feedback it cannot dose clutch torque and will normally take clutch A out of service. P28CE and P28CF describe a signal stuck at the low or high end, P28D0 a value that is in range but wrong. No manufacturer publicly documents P28CD.

Likely causes

Open signal, 5-volt supply or ground wire of the clutch A pressure sensor
Sensor connector not fully latched or pin pushed out
Internal open in the pressure sensor

Symptoms

  • Clutch A shut off, half of the gears unavailable
  • Transmission warning lamp and stored code

Repair estimate

DifficultyHardWorkshop job
Parts and labour€80–1,000
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

clutch pressure sensor awiring harnesstcm

Related codes

P28CEP28CFP28D0P28DC

References: law.cornell.edu, cti-symposium.world.