What P07A4 means
Each friction element (clutch or brake) has three functional codes: slip while commanded locked (P079A ff), performance/stuck off – it does not apply or applies too weakly – and stuck on – it does not release.
How the engine computer detects it
P07A4 concerns clutch B. Only Ford's DPS6 PowerShift dry dual-clutch uses it, for clutch B – input shaft 2 with reverse and gears 2, 4 and 6 – as 'functionally stuck off', next to the electrical codes of the clutch B actuator; Ford publishes no thresholds. GM's hybrids report clutch 2 only as slip (P079B) or stuck on (P07A5). A clutch that does not apply means missing even gears or reverse and limp mode.
Written from public technical sources and not yet checked by a mechanic. How we write these pages
Symptoms
- Check engine light or transmission warning
- Gear missing or slipping, weak acceleration
- Limp mode
Common causes
- Clutch B plates worn or piston seal leaking Most likely
- Too little apply pressure (fluid, pump, valve) Possible
- Clutch actuator or valve sticking (DCT: electric actuator) Possible
- Module software or lost adaption Less likely
How to diagnose P07A4
- Read every stored code with an OBD-II scanner. If misfire or fuel trim codes are there too, fix those first: they often cause this one.
- Inspect the parts involved: transmission clutches, transmission valve body, hybrid control module.
- Work through the causes above from most to least likely, cheapest checks first.
- Clear the code and drive a full drive cycle to confirm the repair held.
Reading the code
- P
- Powertrain
- 0
- Generic (SAE) code
- 7
- Transmission
- A4
- Specific fault
Questions drivers ask
Can I drive with code P07A4?
If the car shifts normally, drive gently to a shop. If it's stuck in one gear, slips, shifts harshly or won't move out of Park, don't drive it: have it towed.
Will my car pass an emissions inspection with P07A4?
Probably not in states that test vehicles with an OBD-II scan: an emissions-related code that keeps the check engine light on is usually an automatic fail. Rules differ by state and county, so check yours.
This page is general information, not a substitute for a professional diagnosis. Repair costs are rough estimates for parts and labor and vary by vehicle and region.