What it means
Clutch B takes longer than calibrated to reach the engaged state. Hydraulic flow restricted or pressure rise too slow.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Clutch B engages to transfer torque through the transmission, with hydraulic flow controlling how quickly it applies. The transmission module monitors Clutch B pressure rise and engagement time; this code sets when the clutch takes longer than calibrated to reach its engaged state.
Common causes
Most likely first.
- Hydraulic flow restricted upstream
- Increased friction in clutch actuator
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 the freeze-frame and transmission data, then check commanded versus actual Clutch B pressure and engagement time to confirm the slow application.
- Check fluid level and condition, since low or unsuitable fluid can slow hydraulic pressure rise.
- Inspect the transmission connector and accessible wiring for damage or poor connections affecting Clutch B pressure control.
- Use a scan tool to compare Clutch B commanded and actual pressure during engagement and look for a delayed pressure rise.
- If the pressure rise is slow, test hydraulic flow upstream and inspect the Clutch B actuator for excess friction using the manufacturer's procedure.
Common fixes
- Correct transmission fluid level or service fluid as specified by the manufacturer.
- Repair damaged wiring or a poor connector connection affecting Clutch B control.
- Clear a restriction in the hydraulic supply path to Clutch B.
- Repair or replace a Clutch B actuator with excessive internal friction.
Can I keep driving?
Avoid hard acceleration and towing while shifts are delayed; prolonged engagement can cause slipping, shudder, and clutch heat and wear. If drive is lost or limp mode engages, stop safely and arrange service.
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.