In order to prevent an unintended rollaway situation, modern vehicles are equipped with something called a gear shift lock solenoid. When the computer detects that all of the conditions are met (foot is on the brake pedal, gearshift lock button is depressed) for safely shifting the vehicle out of Park, the gear shift interlock solenoid will release and allow the transmission to be shifted into gear. A P0928 DTC means that there is an electrical problem on the control circuit for this solenoid.
How Serious is the Code?
Obviously a P0928 diagnostic trouble code is pretty serious, because it probably means that you will be able to drive your vehicle.
Symptoms of a P0928 include:
- Transmission cannot shift out of Park
- Low or dirty transmission fluid
- Low battery voltage
- Bad fuse(s) or fusible link(s)
- Damaged wiring or connectors
- Failed gearshift lock solenoid
- Failed brake light switch
How to Diagnose the Code?
Diagnosing a P0928 OBDII trouble code should start with a thorough examination of the wiring and connectors related to the gear shift interlock solenoid (it’s possible that there may be a shorted wire, or liquid damage if something got spilled around the shifter). The battery voltage, fuses, fusible links and relays should all be tested as well. The brake light switch should also be considered, along with the condition of the transmission fluid.
What Repairs Will Fix P0928?
- Change the transmission fluid/filter
- Charge or replace the battery
- Replace any blown fuses or fusible links
- Replace any damage wiring or connectors
- Replace gear shift interlock solenoid
- Replace brake light switch