Powertrain, generic (extended)

P28E3 Shift Motor Phase U-V-W Performance

Check engine lightOn
EmissionsNot relevant
Drive cycleRequired
Limp modePossible

P28E3 covers the phase circuits of the shift motor when none of them is clearly open or shorted, yet they do not behave as expected: one phase draws noticeably more or less current than the others, or the current pattern does not match the commutation step. Such an imbalance comes from a phase with raised resistance, a partly shorted winding or a weak switch in the driver, and it shows up as uneven torque. No manufacturer documents P28E3 publicly. A Denso shift range patent describes the motor driver that energises U, V and W according to the rotor position and stops the motor at a target encoder count; Hyundai Kefico builds its SBW actuator around a brushless motor. CARB requires functional checks on outputs. Range changes may be slow, noisy or refused.

Likely causes

Corroded or loose contact raising the resistance of one phase
Partly shorted turns in a motor winding
Degraded switch in the motor driver

Symptoms

  • Shift system warning in the cluster
  • Slow or noisy range changes
  • Occasional refusal to change range

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

P28E0P28E1P28E2P28E5

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