In short
To remap a BMW or a MINI you first need to know which engine it has: since the 2014 generation, MINIs use the same three- and four-cylinder B-series engines as BMW, whereas earlier ones in many versions had an engine shared with the PSA group. Recent BMW ECUs (Bosch MG1 on petrol and MD1 on diesel) usually have to be removed and, often, opened. If the car is an automatic, it almost always has an eight-speed ZF gearbox with its own control unit. ECU remapping from from €200 + VAT (€242 including VAT), in Alcalá de Henares or we come to you anywhere in the Community of Madrid (the Madrid region).
Why a current MINI is, underneath, a BMW
Since the generation that arrived in 2014, MINIs share with front-wheel-drive BMWs (the 1 Series and 2 Series on that architecture, X1, X2) the platform and the modular B-series engines: three-cylinder (B38 petrol, B37 diesel) and four-cylinder (B48 and B47). A Cooper S and a BMW with the same engine have ECUs from the same family and are worked on in the same way.
The previous generation is a different story. Many pre-2014 MINIs had petrol engines developed jointly with the PSA group, which were also fitted to Peugeots and Citroëns, and some diesel versions were also of PSA origin. That's why, on a MINI, the first thing we ask you is the year and the engine: it changes the ECU, the reading method and what we check beforehand.
DME and DDE: when the ECU has to be opened
BMW calls the petrol engine ECU the DME and the diesel one the DDE. What matters when remapping is its generation:
| Era and engines | Usual ECU | How it's normally worked on |
|---|---|---|
| N47 and N57 diesel (before the B series) | Bosch EDC17 | Diagnostic socket or bench, depending on the software |
| N20, N55 and similar petrol | Bosch MEVD17 | Diagnostic socket or bench; some versions, by opening it |
| B37, B47 and B57 diesel | Bosch MD1 | Removed; often, opened |
| B38, B48 and B58 petrol | Bosch MG1 | Removed; often, opened |
On recent MD1 and MG1 units, BMW protects the memory, and access through the diagnostic socket doesn't allow modified software to be written. The ECU has to be removed and, depending on the version, opened so we can work directly on the processor. It's delicate work that we prefer to do at the workshop, with the unit on the bench and a stable power supply. If there isn't yet a reliable method for a particular software version, we'll tell you.
Coding a BMW is not remapping it
BMW organises each car's equipment in a vehicle order (called FA in its tools): a list of options the modules look up to know what they have to do. By changing that list and recoding the modules, functions can be activated or retrofitted equipment adapted. That's what's known as BMW coding.
- It doesn't touch the engine software or the power output.
- What can be activated depends on the module, its version and whether the physical hardware is there.
- Before changing anything, we save the coding the car came with.
If what you're after is a specific function, tell us which one and the exact model: some activations are trivial on one series and impossible on another without changing the module.
The eight-speed ZF gearbox
Almost every automatic BMW from the last decade has the eight-speed ZF gearbox (8HP, which BMW markets as Steptronic) on rear-wheel-drive cars. It has its own control unit, which allows adjustments: shift points, how quickly it responds in sport or manual mode and the torque it accepts before protecting itself. If the engine is remapped and the gearbox is left stock, in some cases the transmission limits what reaches the wheels.
On MINIs and front-wheel-drive BMWs, depending on the year, the automatic can be an Aisin torque-converter gearbox or a seven-speed dual-clutch unit. They're different gearboxes and are dealt with separately. We cover it on automatic gearboxes.
The ISN code and starting
A BMW's engine ECU and the module that manages access and starting (CAS on earlier models; FEM or BDC on later ones) share a pairing number called the ISN. If it doesn't match, the engine won't start even with a good key. This explains two common situations:
- A scrapyard DME or DDE won't work without adapting the ISN: the ECU has to be cloned or the pairing rewritten.
- To make a new key, the access module has to be read, and on some models that means removing it. We explain it on keys.
Before remapping a BMW or a MINI
- Timing chain: on some N-generation engines (such as the N47 diesel or the N20 petrol) it's a known weak point. If it rattles on a cold start, that gets checked first.
- Coils, spark plugs and injectors on turbocharged petrol engines: a misfire that's mild today becomes more noticeable with more demanding software.
- Automatic gearbox oil: if it jerks or slips, the gearbox comes first.
- Warning lights and faults: no outstanding faults in any control unit, as with any Stage 1.
The ITV, insurance and warranty side is the same as for any other make: you'll find it on legality, ITV and insurance.
Send us the model, the engine if you know it, the year and whether the gearbox is manual or automatic. We'll tell you which ECU it has, how it's worked on and the price.
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