P28E1 code meaning
Shift Motor Phase U-V-W Circuit High
Powertrain system Generic code P28xx codes Check engine light
What P28E1 means
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.
P28E1 at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyHard
- Typical labor1 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P28E1
- Shift system warning in the cluster
- No response to the gear selector
- Vehicle may remain in Park
Common causes of P28E1
- Most likelyPhase lead shorted to a battery-voltage wire in the harness
- PossibleHigh-side switch in the shift control unit stuck on
- Less likelyWater or corrosion bridging pins in the actuator connector
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Shift motorShift motor position sensorTCM
What each part of P28E1 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. |
| E1 | The exact fault in that area. |
What to do next
- Note P28E1 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 P28E1
What does P28E1 mean?
P28E1 means "Shift Motor Phase U-V-W Circuit High". 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. It is a generic code, so it means the same on every make.
Is it safe to drive with P28E1?
Drive gently and only to a workshop. With P28E1 the car can go into limp mode (reduced power) to protect itself.
Will P28E1 fail an emissions test?
P28E1 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P28E1 to fix?
Difficulty: hard. A typical repair takes 1 to 4 hours of work. This is a job for a workshop.
Will P28E1 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.