P0928 Gear Shift Lock Solenoid Control Circuit/Open

P0928 indicates a gear shift lock solenoid control circuit or open-circuit fault. The shift-lock solenoid command path is incomplete or unavailable.

Code details

Generic OBD-II · P0

System: Transmission
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not bypass the shift-lock system; it is a safety function and the solenoid circuit should be repaired.

Symptoms of P0928

Harsh, delayed, or slipping shifts, or being stuck in one gear.
Check-engine light, sometimes with limp-home mode.
Flaring RPM or a shudder under load.

Common causes of P0928

Low or degraded transmission fluid.
A failing speed sensor, shift solenoid, or pressure-control circuit.
Wiring, connector, or internal hydraulic/mechanical faults.

Useful checks before replacing parts

Check shift-lock solenoid feed voltage, ground control, resistance, connector fit, brake switch input, and circuit continuity under load.
Inspect shifter wiring, console connector condition, fuse or relay supply, spilled-liquid damage, and module driver output.
Compare brake pedal data, park/neutral state, shift-lock command, and actual shifter release behavior during the fault.

Related OBD-II codes

These nearby transmission entries can help compare wording and pin down the fault area.