BMW Key Replacement in Milwaukee

BMW keys for the 3 Series, 5 Series, X3, and X5

BMW key replacement in Milwaukee starts with one question: which module in your BMW keeps the key list. The model and the year answer it. We make keys for the 3 Series and 5 Series, the 1, 2, and 4 Series, the X1, X3, and X5, and many other models, and we program them at the car, whether it sits in a garage in Mequon or a lot in Brookfield.

Four generations of BMW key systems

BMW changed its key system about every ten years, and each generation is programmed in its own way.

The oldest is EWS, a small immobilizer box used up to the mid-2000s, for example in the 1999–2006 3 Series, where the key still turns in a normal ignition. Then came CAS, the Car Access System, used in the E-series cars of the mid-2000s and early 2010s, such as the E90 3 Series, the E60 5 Series, and the E70 X5, and in an updated form in the 2011–2016 5 Series. In many CAS cars, the key goes into a slot in the dash, and the Start/Stop button starts the engine.

The F30 3 Series from 2012, the 1 and 2 Series, and the 4 Series moved the key list into the FEM, the front electronic module. From 2014, the BDC, the body domain controller, took over in the X5, then in the X1, the X2, and the G-series models that followed.

What the module means for your visit

On most CAS cars, we program the key through the diagnostic port without taking anything apart. On many FEM and BDC cars, the module comes out of the car for a bench read, the data goes to the programming tool, and the module goes back in before the key is added. When every key is lost on a FEM or BDC car, the engine computer's security code can also be needed, and reading it can mean removing the engine computer as well. That is why a BMW key takes from 45 minutes to 2 hours, and the longer end is the FEM or BDC car with no key.

Comfort Access and smart keys

BMW calls its keyless entry Comfort Access: with the key in your pocket, touching the door handle unlocks the car. On F-series and G-series BMWs, the engine starts with the Start/Stop button as long as the key is inside the car, with or without Comfort Access. A new key has to match the car's radio frequency and its key type, so the year, the model, and a photo of your key help us bring the right one. Every BMW smart key carries a small emergency blade for the driver's door.

A spare BMW key

With a working key, a spare BMW key starts at $249 (spare car key). We read the module, prepare a key for your car, program it, and test the start, the doors, and the buttons. A BMW keeps a numbered list of its keys, and a key that went missing can be switched off in that list, so it stops starting the car even if someone finds it.

When every BMW key is lost

No key at all means we open the car first (car lockout). The emergency blade is cut from a decoded lock or by code after we check the title or registration. Then the module is read and the new keys are added, with the engine computer code where the car needs it. All keys lost on a BMW costs more than a spare and takes longer, and we give you both the price and the time before we start (lost car keys).

Newer BMWs

BMW keeps updating the BDC in its newest models. For a BMW from 2019 or newer, send us the year, the model, and the VIN, and we tell you before the visit what the key takes and what it costs. Asking first costs nothing.

For other European makes, see Audi keys, Volkswagen keys, and Mercedes-Benz keys. For a Japanese luxury car, see Lexus keys, and for every make, car keys by make.