P0757: Shift Solenoid "B" Stuck On
Shift solenoid B stays on when it should be off.
High risk
Usually drivable, but shifting may be wrong or the gearbox may hold one gear. Have it checked soon.
Short answer · Can I keep driving with P0757?
Usually yes, at moderate speed. The gearbox may skip gears, shift harshly or stay in a fixed gear. Have it checked soon.
What does P0757 mean?
P0757 means the transmission control unit sees the gear behaviour of a solenoid that stays open even when it is switched off. A solenoid stuck open, a sticking valve, debris in the fluid or a short that keeps the solenoid powered are typical causes. Which gears are affected depends on the transmission design.
What the car does when the code is set
The check engine or transmission warning comes on. You may notice slipping, flare when shifting, late engagement or the transmission staying in one gear.
How the system works
In each gear, an automatic transmission has a known ratio between its input and output speed. The transmission control unit compares the measured speeds with the expected ratio for the gear it has selected. If they do not match, a clutch or band is slipping, a shift has not been completed, or a speed signal is wrong. To protect the transmission, the control unit may lock it in one gear (limp mode) until the fault is cleared.
Common symptoms
Possible causes
Listed without ranking. The cause on your car depends on make, engine and mileage — see the maker notes below.
- Low or degraded transmission fluidClutches slip if the pressure is low.
- Worn clutches or bandsInternal wear lets the transmission slip.
- Faulty shift solenoids or valve bodyPressure is not controlled correctly.
- Speed sensor problemWrong speed readings give a wrong ratio calculation.
How it is diagnosed
- Check the fluidCheck level, colour and smell. Burnt fluid points to internal wear.
- Read gear ratio dataLive data shows which gear the ratio does not match.
- Check solenoids and sensorsTest them electrically and check other transmission codes.
- Pressure testA workshop measures line pressure to find internal problems.
Questions about P0757
Can fresh fluid fix P0757?
If dirty fluid made a solenoid or valve stick, a fluid and filter change can help. If the code returns, the solenoid or valve body is checked.
Will a fluid change fix it?
Only if old or low fluid is the cause. If clutches are worn, new fluid may help for a short time only.