Powertrain, generic (extended)

P28E1 Shift Motor Phase U-V-W Circuit High

Check engine lightOn
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

P28E1 is the opposite of P28E0: on any of the three shift motor phases the controller sees a voltage that is higher than the switching state allows, for example while the low-side switch should pull it down. Likely reasons are a phase lead touching a battery-powered wire, a winding with an internal short to a live part, or a high-side switch in the driver that no longer turns off. No manufacturer documents P28E1 publicly. The hardware is the same as described in a Denso shift range patent, where a motor driver feeds the U, V and W phases and a relay can disconnect the motor, and in Hyundai Kefico's brushless SBW actuator. CARB requires circuit checks on outputs. With a phase held high the motor cannot be commutated, so range changes stop.

Likely causes

Phase lead shorted to a battery-voltage wire in the harness
High-side switch in the shift control unit stuck on
Water or corrosion bridging pins in the actuator connector

Symptoms

  • Shift system warning in the cluster
  • No response to the gear selector
  • Vehicle may remain in Park

Repair estimate

DifficultyHardWorkshop job
Parts and labour€150–1,500
Time1–4 h

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

Parts involved

shift motorshift motor position sensortcm

Related codes

P28E0P28E2P28E3P28E4

References: law.cornell.edu, patents.google.com, hyundai-kefico.com.