Try telling my dealer that They told me it's impossible even though I gave them info on dealers that had supposedly done it. I then get told that BMW have disallowed this coding as it's a chargeable factory option. My argument was that it's a safety issue but I got nowhere. The only possiblity was to buy a £500 SES module.

So, NavCoder and an i-bus interface had it activated in 30 seconds flat. Demonstrated to the Service Manager who just shrugged and said it was an unofficial modification FFS!

I'd be interested though to hear of anyone else who has actually got their dealer to code the option officially via Retrofit coding, and whether that actually then shows the vehicle as having SA620.