Bosch engine control units for Audi
We supply used Bosch engine ECUs for the Audi A1, A3, A4, A5, A6, A8, TT and Q7, each tested before dispatch. The range covers petrol engines – from 1.4 TSI and 1.8T, through 2.0 TFSI, up to the 4.2 FSI V8 – and 2.0, 2.7, 3.0 and 4.2 TDI diesels. More units from this manufacturer are listed under Bosch automotive electronics.
The engine control unit manages fuel metering, ignition on petrol engines, boost pressure and exhaust aftertreatment, and exchanges data with other modules over the CAN bus. The exact scope depends on the engine and the ECU family.
How to choose the right Audi engine ECU
The most reliable method is to compare the full numbers on the label of your original unit. Before ordering, check:
- the Bosch number, e.g. 0261S04417 or 0281016572,
- the Audi/VW OEM number including the final letters, e.g. 8K2907115M or 03L906019AL,
- the ECU family, e.g. MED17.1 or EDC16CP34, if it is shown on the label,
- the software (SW) and hardware (HW) versions, if available,
- the engine code, power output and gearbox type,
- the preparation stated in the listing, e.g. IMMO OFF or for programming.
Numbers that differ by a single letter may indicate different software or configuration, and an identical housing and connectors do not prove the units are interchangeable. The VIN helps identify the vehicle version, but it does not replace the number on the ECU label.
Within the Volkswagen Group some ECUs are used across several brands, and this category also contains units listed for VW / Audi / Seat / Skoda. In these cases too, compatibility depends on the full part numbers rather than the car brand. If you are not sure, send us a photo of the original ECU label and your VIN and we will check compatibility before you order.
Bosch ECU families in our Audi range
Audi has used many Bosch ECU families over the years. The table shows examples from our current stock – it is not a complete list of applications for each family.
IMMO OFF, programming and cloning of Audi ECUs
The preparation method depends on the specific ECU platform. Not every method is available for every part number, so the preparation is always stated in the product description.
IMMO OFF units
On an IMMO OFF unit, the immobiliser function in the ECU is disabled. With a matching variant, the unit does not need to be paired with the car's immobiliser. IMMO OFF does not change hardware compatibility or the ECU configuration, however, so correct part-number matching is still essential. Some listings state additional conditions, such as the need for a working original key.
On some newer Audi systems, a SAFE message or a stored immobiliser fault may remain on the instrument cluster after fitting an IMMO OFF unit, even though the engine starts and runs normally. This can happen because other modules in the car still check authorisation. The result depends on the vehicle generation and the ECU version.
Programming, cloning and VIRGIN
- Programming and adaptation – matching the ECU to the vehicle using suitable diagnostic equipment or a programmer.
- Cloning – transferring data from the original ECU to a compatible replacement unit. This requires the data to be read correctly from the old unit, which may not be possible after heavy corrosion or memory damage.
- VIRGIN – preparing selected units for fresh adaptation in the vehicle. Not every unit can be prepared this way.
Examples of Audi engine ECUs in stock
All available part numbers are shown in the product list above. Compare them with the label on your own ECU before ordering.
Audi Q7 engine ECUs
The largest group in this category are ECUs for the Audi Q7 4L with 3.0 TDI, 4.2 TDI and 4.2 V8 engines. The 4.2 TDI uses two engine ECUs in a Master and Slave arrangement – we offer both single units and sets of two ECUs prepared IMMO OFF. Details and the full list of part numbers are in our Audi Q7 ECU collection.
On the Audi Q7 4L, a common cause of ECU failure is water collecting under the scuttle panel when the drains are blocked. We describe a typical case in our guide to the water-damaged 0281013691 / 4L0910401K ECU in the Audi Q7 3.0 TDI. Fix the cause of the water ingress before fitting a new unit so that it does not get damaged again.
Symptoms of a faulty Audi engine ECU
An ECU fault can show up in different ways. The most commonly reported symptoms are:
- the engine will not start,
- no diagnostic communication with the ECU,
- limp mode and reduced power,
- rough running or stalling,
- CAN communication faults stored in several modules,
- problems after interrupted programming,
- signs of moisture, corrosion or damaged connector pins.
Similar symptoms can be caused by faulty sensors, wiring, power supply, earths or fuses. No communication does not always mean the ECU is faulty, so we recommend diagnosing the vehicle before buying.
Testing, warranty and delivery
Every ECU is bench-tested before dispatch, connected to a power supply and diagnostic tools outside the vehicle. We also have test vehicles – ECUs for the Audi Q7 are additionally checked in our own Audi Q7 test car. Testing the unit does not, however, replace diagnosing your vehicle or finding out why the original ECU failed.
Warranty terms are stated in the product description, and the return and complaint procedure is on the returns and complaints page. Shipping information is on the delivery times and costs page, and the available payment options are listed under payment methods.
FAQ – Audi engine ECUs
