OBD2 CODE

P0871 Transmission

We do not have a full sheet for this code yet, with its causes and checks. What you see here comes from the OBD2 code standard.

Official name (SAE): Transmission Fluid Pressure Sensor/Switch C Circuit Range/Performance
System: Engine and transmission (P)
Group: Transmission
Code type: Generic code: it means the same on every make.

Name taken from the open OBDex code list (public domain).

What do I do now?

If the engine light flashes, the car loses a lot of power, overheats or the brakes fail, stop somewhere safe and call for assistance.
If the car drives normally, book a garage and show them this code: its exact meaning and the cause depend on each model.
Tell us what you notice: the diagnosis takes the code, your car and the symptoms into account.

A generic X-ray car with this code's area marked in red: transmission. It is a guide, not the layout of your model.

DQ250 DSG mechatronic and oilDSG gearbox

Engine / equipment: DQ250 6-speed wet-clutch DSG (2.0 TDI, 2.0 TSI and other powerful engines in the Golf, Passat, Tiguan, A3, TT, Octavia, Superb, Leon…)
Period mentioned: 2003–2020
Symptoms: Jerking or shudder when pulling away and at low speed, harsh shifts, gearbox warning or limp mode; codes P17BF, P189C, P0841, P0871 or P0717.
Possible cause described: In most cases the cause is the mechatronic unit (the electro-hydraulic control unit), not the clutches. The oil shares a circuit with the clutches and degrades, carrying debris that damages the valves; the pan can also rust and leak. Volkswagen specifies an oil and filter change every 60,000 km.
Check for the garage: Read codes with ODIS or VCDS, check the oil change history, inspect the pan for rust or leaks and the clutch adaptation values. Replacing the mechatronic control board is often enough.
Cost cited in the source: Oil and filter change: maintenance every 60,000 km; control board or mechatronic: expensive repairA rough figure from the original database, not an up-to-date quote.

Mileage cited in the database: from 60,000 km. This is not a maintenance interval and does not predict a failure.