Convertible Roof Modules (CRMs) in Aston Martins produced between 2006 and 2015 are well-known for developing faults—unfortunately, replacements are exceedingly expensive, often exceeding £1,000 in the UK. My own 2007 V8 Vantage suffered this failure, and after purchasing a used module, I discovered it exhibited precisely the same fault as the original. With two non-functional units in hand, I decided to investigate further. Ultimately, I found that both modules had failed for the exact same reason—one that can be remedied at minimal cost.

Through testing, I identified the issue as originating in the MCU (microcontroller unit), the main processor on the board. Cooling the MCU—such as by briefly placing the module in a freezer—would temporarily restore operation, indicating a thermal-related internal failure. The proper solution is to replace the MCU, which has likely degraded over time due to ageing of its silicon structure.
Although MCU replacement is not a trivial task for everyone, it is entirely achievable for anyone equipped with the necessary tools and possessing basic SMD soldering skills.

Required components and tools:

• Replacement MCU (commonly available on AliExpress): MC9S12DG128VFUE — confirm that the serial number matches the MCU in your module.

• xProg 5.55 (commonly available on AliExpress) — used to read and write the secured Flash and EEPROM memory to and from the MCU.

The repair procedure involves desoldering the original MCU from the CRM board and mounting it onto the adapter board supplied with the xProg. You must then read the Flash and EEPROM contents. Afterward, place the new MCU onto the same adapter board and write the previously extracted data to it. Once programmed, solder the replacement MCU back onto the CRM board—and the module should be fully operational.

I completed this repair on my own module approximately half year ago, and it has been functioning flawlessly ever since.


Opened module.

XProg

Writing data to new MCU

MCU connection with XProg