- The vehicle does not start.
- Malfunction message on the iDrive screen.
- Key not recognized.
- The car will turn over but not start.
- Low or overvoltage of EWS module.
What is the BMW CAS module?
CAS stands for the Car Access System. Two of the main functions of the BMW CAS module include:
CAS module generates random key code every time the vehicle is started and synchronizes the code with the Engine Control Unit, which BMW calls DME or DDE.
When a defective BMW CAS control unit is replaced, it needs to be programmed if the module is new (virgin).
If a used BMW CAS module is installed, the Engine Computer (DME) and key need to be replaced with those from the donor car.
List possible symptoms you may notice if the CAS module or one of its components fails.
What is the CAS module in BMW and MINI?
CAS stands for the Car Access System. Among other things, two of the main functions of the BMW CAS module include:
CAS module generates random key code every time the vehicle is stared which it synchronizes with the Engine Control Unit, which BMW calls DME or DDE. If you have a deffective CAS module, you vehicle may show some of the symptoms below.
The CAS serves as an antitheft alarm system and enables the start of BMW vehicles. A transponder chip is integrated in each of the vehicle keys. A ring coil is fitted about the ignition lock. The transponder chip is powered by this coil from the CAS control module. This means that no battery is necessary in the key. The power supply and data transfer take place in the same way as a transformer between the loop antenna (coil) at the ignition lock and the transponder chip. The key then sends data to the CAS control module. If these data are correct, the CAS control module enables the starter by means of a relay located in the control module and additionally sends a coded start enable signal via a interface to the DME/DDE. These procedures may result in a start delay of up to half a second.
The value of these codes changes after every start procedure. Start enable only takes place if the code sent by the CAS control module matches with the code stored in the DME/DDE control module. The control modules are allocated only during initial programming of the DME/DDE control module. The engine control module then adopts the rolling code of the CAS control module, process called Synchronization. EWS4 Mode
FAQ
What is CAS control?
What is CAS in a car?
