What it means
The transmission control module monitors how long friction element H takes to apply. This code sets when the measured apply time falls outside the expected range.
At a glance
- Usually lights the check-engine light
How it works
Friction element H is an internal transmission clutch or other friction unit used to engage specific gear paths. The TCM tracks the time it takes element H to apply and sets P273B when that apply time is outside the expected range, often because of wear, pressure-control drift, or leakage in its hydraulic circuit.
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 data and note the gear, temperature, and shift event when P273B set; scan for related codes.
- Check transmission fluid level and condition using the manufacturer's procedure, since poor fluid condition can affect element H's application.
- Use scan-tool data to identify shifts that use friction element H and look for delayed engagement or slip during those shifts.
- Inspect the relevant pressure-control solenoid wiring and connectors for damage, corrosion, or loose contacts.
- Check pressure-control operation and line pressure according to the manufacturer's procedure if basic electrical and fluid checks pass.
- If external controls are functioning, assess the internal apply circuit and friction plates for element H wear or hydraulic leakage.
Common fixes
- Correct low or degraded transmission fluid using the specified service procedure.
- Repair wiring or replace a pressure-control solenoid if testing shows it is causing element H's apply delay.
- Repair an internal hydraulic leak in element H's apply circuit.
- Replace worn friction plates in element H if confirmed by inspection.
Can I keep driving?
Avoid heavy loads and hard acceleration if shifts involving element H slip, shudder, or are delayed; continued slipping can overheat the transmission. Stop if drive becomes unreliable or the transmission locks into a restricted gear.
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.