Sticking or faulty shift solenoid or pressure control solenoid keeping Element A applied; Valve body wear, sticking valves or debris blocking the hydraulic circuit; Degraded, contaminated or incorrect transmission fluid, or wrong fluid level; Wiring or connector fault in the solenoid circuit causing it to stay energised; Mechanical failure of the clutch or brake pack, such as burnt or welded plates or a seized piston; Faulty speed sensor giving false slip readings; Transmission control module fault or outdated software calibration.

P07A3

Transmission Friction Element A Stuck On.

Generic
Powertrain
Generic code
High severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
7: AreaTransmission
A3: FaultThe specific fault in that area

What it means

P07A3 means the transmission control module has detected that Friction Element A, a clutch or brake pack inside the automatic gearbox, is stuck on (engaged) when it should have been released. The module saw gear ratio, shaft speed or slip readings that did not match the commanded gear, which points to the element staying applied. Which physical clutch or brake is 'Element A' depends on the model and gearbox, so the exact location must be checked in the manufacturer's information.

Symptoms

Gearbox warning light or malfunction indicator lamp on
Harsh or flared shifts, or a shift that fails to complete
Engine braking, drag or shuddering when pulling away, as if two gears are engaged
Gearbox stuck in one gear or in limp-home mode
Stalling or juddering when coming to a stop
Poor acceleration or reduced top speed

Possible causes

Sticking or faulty shift solenoid or pressure control solenoid keeping Element A appliedlikely
Valve body wear, sticking valves or debris blocking the hydraulic circuitlikely
Degraded, contaminated or incorrect transmission fluid, or wrong fluid levellikely
Wiring or connector fault in the solenoid circuit causing it to stay energisedpossible
Mechanical failure of the clutch or brake pack, such as burnt or welded plates or a seized pistonpossible
Faulty speed sensor giving false slip readingspossible
Transmission control module fault or outdated software calibrationrare

How to diagnose

Read all stored and pending codes and note the freeze frame data, including gear commanded, speeds, fluid temperature and load when the fault set
Check for any other transmission or speed sensor codes, and check for manufacturer technical service bulletins for the model
Check the transmission fluid level, condition and smell, following the correct procedure and temperature for that gearbox
Inspect the wiring and connectors to the transmission for damage, corrosion, chafing or fluid ingress
Using live data, compare commanded gear with input and output shaft speeds and slip to see when the element is staying engaged
Test the solenoid circuit and resistance against the manufacturer's specification, and check the speed sensor signals
Carry out the manufacturer's pressure tests or solenoid actuation tests where the model allows
If the fault remains, remove the valve body or gearbox for inspection of the solenoids, valves and clutch packs

How to fix

Correct the fluid level, or replace degraded fluid and filter using the specified fluid type
Repair or replace damaged wiring, connectors or terminals in the solenoid circuit
Replace the faulty shift or pressure control solenoid
Clean, repair or replace the valve body if it is worn or contaminated
Overhaul or replace the gearbox if the clutch or brake pack is mechanically damaged
Update or reflash the control module software only if a known fault is covered by a manufacturer bulletin, and replace the module if it is proven faulty

Can I keep driving?

High severity

Avoid driving until it has been checked, as a clutch or brake pack that stays applied can overheat and cause expensive gearbox damage. If the car must be moved, keep it to a short, gentle trip at low speed.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.