BMW Car Access System (CAS) Module Repair

Resolving "No-Start" Issues After a Collision

The **BMW Car Access System (CAS) Module** is the core of your vehicle's immobilizer and key fob authentication system. After an accident, the module is highly susceptible to overvoltage spikes from damaged wiring or—due to its location in the footwell—from water damage. A compromised CAS module can prevent your car from starting, recognizing your key, or even turning on the ignition. Our mobile service in London provides a safe, accurate, and on-site solution to diagnose and repair these critical faults.

Module Name	Description	Why It Gets Damaged in Accidents	Affected Models (Examples)
Car Access System (CAS) Module	Handles key fob, immobilizer, and start-stop integration with hybrid systems.	Overvoltage or water damage post-impact prevents starting; sync issues with DME.	All models (e.g., 330e, 550e)

Our Specialist On-Site Diagnostics Process:

We provide a crucial first step in the repair process by bringing our expertise directly to your car's location.

• Advanced Diagnostic Scan: We use specialised OEM-level software to read deep-level fault codes from the CAS and other modules like the DME, which helps us pinpoint the exact cause of the communication breakdown.
• Water & Physical Damage Inspection: We perform a thorough visual inspection of the module, its housing, and wiring for any signs of water intrusion or physical impact damage that may have occurred during the collision.
• Module Data Reset & Sync: In many cases, a crash or electrical spike can corrupt the CAS module's data. We can often perform a professional data reset and re-synchronize the CAS with the DME and your key, restoring the system's functionality without a costly replacement.
• Expert Report: We will provide a comprehensive report detailing our findings and an honest recommendation. If the CAS module is physically damaged beyond repair, it will need to be replaced and coded at a specialist workshop. Our mobile service provides the accurate diagnosis you need to make an informed decision.

Safety Note: Your safety is our top priority. A malfunctioning CAS module can leave you stranded. Our service ensures a professional diagnosis from a qualified technician, giving you peace of mind.

Book Your On-Site CAS Module Check

Fill out the form below to schedule a mobile diagnostic visit in London. We will contact you to confirm the details and provide a professional assessment of your vehicle's condition.