What it means
Pressure control solenoid B shows intermittent electrical or hydraulic dropouts — vibration, loose connector, or contaminated ATF that occasionally restricts the regulator port.
At a glance
- Usually lights the check-engine light
How it works
Pressure control solenoid B regulates transmission line pressure in response to TCM commands. This code sets when its electrical signal or hydraulic response drops out intermittently, often as a loose connection or vibration-sensitive harness fault comes and goes.
Common causes
Most likely first.
- Loose connector at the transmission
- Connector with intermittent contact under vibration
- Harness routed against vibrating component
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
How to diagnose it
- Save freeze-frame data and transmission codes before clearing anything, since an intermittent solenoid B fault may not be present during inspection.
- Inspect the transmission connector and harness routing for loose pins, corrosion, fluid intrusion, chafing, or contact with vibrating parts.
- Check solenoid B circuit continuity and coil condition using the manufacturer's procedure, then repeat while gently moving the harness to reveal dropouts.
- Review live data for solenoid B command and feedback during a road test or controlled operating check that reproduces the recorded conditions.
- Check fluid condition and inspect the valve body if electrical checks are stable but the pressure response still drops out intermittently.
Common fixes
- Secure the transmission connector and reroute or fasten the harness away from vibrating or sharp components.
- Clean or repair corroded, loose, or damaged connector terminals.
- Repair intermittent opens or shorts in the solenoid B wiring.
- Service contaminated transmission fluid and inspect the valve body if hydraulic restriction is found.
- Replace pressure control solenoid B if it fails repeatable electrical or operating tests.
Can I keep driving?
Intermittent faults can return suddenly and cause harsh shifts, slipping, or limp mode, so avoid towing and long trips until the cause is found. Stop driving if the transmission begins slipping or cannot shift predictably.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.