What is OEM number 8T0-959-793-N and which part does it identify?

OEM number 8T0-959-793-N identifies the front left door control unit for the Audi A4 B8 (8K2) and the related Audi A5 (8T) model family. The part fits vehicles built between 2007 and 2017, and it is specific to the front left door position, meaning the front right side uses a different control unit under a separate OEM number. It is also known as the comfort control module, since it manages window, exterior mirror, and central locking functions from the front left door. Superseded number: 8T0959793B. OEM number 8T0-959-793-N may fit additional vehicle models not listed here, so always verify against the OEM number on your existing part.

Does OEM number 8T0-959-793-N fit my vehicle?

OEM number 8T0-959-793-N fits the Audi A4 B8 (8K2), built between 2007 and 2015, across petrol and diesel engine variants. The same part also fits the closely related Audi A5 (8T) model range, which shares the B8 platform and door hardware with the A4 B8.

The part is gated by door position rather than by engine or drivetrain: it is built exclusively for the front left door, and the front right side requires a different control unit ordered separately under its own OEM number. Later production runs of the same door position used revised suffixes, such as 8T0959793P and 8T0959793Q, so the printed suffix on the original unit should be checked against the vehicle's parts records before ordering, particularly for vehicles near the end of a model year run.

Audi A4 B8 (8K2), 2007 to 2015, fits across the 1.8 TFSI, 2.0 TDI, 2.0 TFSI quattro, and 2.7 TDI engine variants, since the door control unit is not engine-specific. Audi A4 B8 Avant (8K5) RS4 quattro, 2012 to 2015, uses the same front left unit. Audi A5 (8T3) 2.0 TDI, 2009 to 2012, and Audi A5 Convertible (8F7) S5 quattro, 2009 to 2017, share the identical fitment. Audi A5 Sportback (8TA), 2009 to 2017, fits across the 1.8 TFSI, 2.0 TDI, and 2.0 TDI quattro variants.

OEM number 8T0-959-793-N may fit additional vehicle models not listed here. Always verify by checking the OEM number printed on your existing part.

Fits: Audi A4 B8 (8K2), 2007-2015, all engine variants; Audi A4 B8 Avant (8K5), 2012-2015; Audi A5 (8T3), 2009-2012; Audi A5 Convertible (8F7), 2009-2017; Audi A5 Sportback (8TA), 2009-2017 — front left door position only, later suffixes (8T0959793P, 8T0959793Q) apply to later production runs
Does not fit: Front right door position, which uses a separate OEM number

How is OEM number 8T0-959-793-N installed?

The front left door control unit is a coded module, and its installation is a bolt-on procedure with mandatory electronic calibration. Fitting requires a VAG-compatible diagnostic tool, such as VCDS or ODIS, to match the replacement unit to the vehicle's electronic control unit (ECU) network and to restore learned settings for window one-touch operation, mirror position memory, and central locking behaviour. Without coding, the window and mirror functions on that door will not respond correctly, and fault codes may be stored in the body control module.

1. Disconnect the vehicle battery before removing the door trim panel.
2. Fit the replacement control unit and reconnect the door wiring harness.
3. Reconnect the battery and run the coding procedure with the diagnostic tool.
4. Test window auto-up and auto-down function on the front left door.
5. Test central locking and mirror fold or adjustment from the affected door.

When should OEM number 8T0-959-793-N be replaced?

Replacement triggers

• Front left window fails to move, or moves only in one direction.
• One-touch auto-up or auto-down function stops working on the front left window.
• Central locking fails to lock or unlock from the front left door only.
• Exterior mirror on the driver's side stops adjusting or folding electrically.
• Intermittent electrical faults on the front left door that correlate with rain or door seal water ingress.
• Fault codes stored in the body control module referencing the front left door control unit.

We used AI to help write this text. We regularly check the information - but cannot guarantee that all data is accurate.