Low, degraded or contaminated transmission fluid restricting solenoid movement; Shift solenoid B sticking mechanically due to debris or varnish; Blocked or dirty transmission filter or valve body passages; Damaged wiring, chafed loom or corroded connector at the solenoid or transmission plug; Worn valve body, stuck shift valve or worn bores causing internal pressure leaks; Faulty transmission control unit or outdated calibration (model dependent); Internal clutch or mechanical wear producing a ratio error that mimics a stuck solenoid.

P0757

Shift Solenoid B Stuck On.

Generic
Powertrain
Generic code
Medium severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
7: AreaTransmission
57: FaultThe specific fault in that area

What it means

P0757 is the generic code for Shift Solenoid B stuck on, meaning the transmission control unit has detected that the solenoid is not releasing as commanded. The control unit compares the commanded gear with the actual gear ratio, calculated from input and output shaft speeds, and sees a mismatch consistent with the solenoid or its hydraulic circuit being stuck in the on position. Which gears are affected depends on the transmission design.

Symptoms

Gearbox warning light or malfunction indicator lamp on
Transmission stuck in one gear or in limp mode
Harsh, delayed or flared gear changes
Wrong gear selected, or a missed shift into certain gears
Poor acceleration or high revs at motorway speed
Reduced fuel economy

Possible causes

Low, degraded or contaminated transmission fluid restricting solenoid movementlikely
Shift solenoid B sticking mechanically due to debris or varnishlikely
Blocked or dirty transmission filter or valve body passagespossible
Damaged wiring, chafed loom or corroded connector at the solenoid or transmission plugpossible
Worn valve body, stuck shift valve or worn bores causing internal pressure leakspossible
Faulty transmission control unit or outdated calibration (model dependent)rare
Internal clutch or mechanical wear producing a ratio error that mimics a stuck solenoidrare

How to diagnose

Read all stored codes and freeze frame data, noting the gear, speed and fluid temperature when the fault set
Check transmission fluid level, condition and smell, following the manufacturer's procedure for that model as some are sealed units
Inspect the transmission wiring and connectors for chafing, oil ingress, corrosion and bent pins
Check for related codes such as other shift solenoid, speed sensor or ratio codes, and for any manufacturer service bulletins
Use live data to compare commanded gear, actual gear ratio and input and output shaft speeds during a road test
Measure solenoid resistance and check supply and control signals against the manufacturer's specification
Check the circuit for shorts to voltage or ground between the solenoid and the control unit
If the electrical side is sound, inspect the valve body, solenoid and filter, and test line pressure where the model allows

How to fix

Correct the fluid level or replace the fluid and filter with the specified type if it is degraded or contaminated
Repair or replace damaged wiring and connectors
Replace the shift solenoid B if it fails electrical or functional testing
Clean or overhaul the valve body, or replace it if it is worn or the passages are damaged
Update or reflash the control unit calibration only if an outdated or faulty calibration is confirmed as the cause
Repair or replace the transmission if internal wear is confirmed

Can I keep driving?

Medium severity

The car can usually be driven carefully a short distance, but the gearbox may be in limp mode and continued use risks further internal damage. Book diagnosis soon and avoid heavy loads or towing.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.