What it means
The time required to apply friction element B (a clutch or band inside the automatic transmission) is outside the expected window. Either too long (worn clutch, low pressure) or too short (sticky valve, mis-calibration).
At a glance
- Usually lights the check-engine light
How it works
The transmission control module tracks the time needed for friction element B, an internal clutch or band, to apply during a commanded shift. This code means element B's apply time is outside its expected window, whether engagement is too slow or occurs abnormally quickly.
Common causes
Most likely first.
- Worn clutch friction plates
- Pressure control solenoid drift
- Internal hydraulic leak in apply circuit
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 and transmission data, and identify the shift event associated with the element B apply-time fault.
- Check transmission fluid level and condition according to the manufacturer's procedure, because fluid loss or deterioration can affect element B pressure.
- Inspect transmission connectors and harnesses for damage or poor contact that could disrupt solenoid control.
- Use a scan tool to compare element B apply-time data with commanded gear changes and pressure-control solenoid operation.
- If the basic checks are inconclusive, test line pressure and the element B apply circuit for pressure-control drift or an internal hydraulic leak before concluding the clutch is worn.
Common fixes
- Correct fluid level or service the fluid if it fails the manufacturer's condition requirements.
- Repair damaged transmission wiring or connector connections.
- Replace a pressure-control solenoid only when testing shows its output is out of range.
- Repair the element B hydraulic circuit or clutch pack if internal leakage or wear is confirmed.
Can I keep driving?
Keep driving to a minimum and avoid towing or hard acceleration, since slipping or harsh shifts can rapidly worsen internal wear. If the transmission loses drive or becomes stuck in a gear, stop safely and arrange recovery.
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.