2011 L320 diesel, does anyone know if the ACE ECU units are plug and play or do they need to be programmed to the car. I suspect mine is faulty and needs exchanging.
Thanks.

They can be used 2nd hand, but need the correct firmware installed

Can you elaborate, my understanding was that the CCF files automatically detect the correct ECU is installed. Not sure what you mean by firmware.
Thanks

The actual firmware/software installed into the ECU. It's different for 2.7/3.6/4.2 models etc. Also different for different model years too

The CCF is completely separate from the ACE firmware

I believe the module has a choice of "tunes" available when it's made and the correct one for the vehicle is selected when it's first installed. So if you have a TDV8, for example, getting a second hand module from a TDV8 should make things easier, especially if you can find the right year.

The different tuning is because the different engines are heavier/lighter and that has an effect on roll which the system has to control. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed