CODE to disable the Start & Stop ?

Hmm........ disabling the Battery Monitor Module (BMM) has been used by some folk on the mk7 as a way of deleting Start Stop (SS) and it does work - but I would caution against this approach because I suspect that it has other consequences. 

On a mk7, this same tweak is implemented by manually unplugging the the 2 x wire connector from the physical BMM that lives on the negative battery lead - see picture below. Unplugging the connector on a mk7 without resulting in an error message on the dashboard is possible because the communication mechanism between the BMM and the master module (which is the hex19 Gateway module) uses LIN protocol. LIN is a slow speed, single wire communications mechanism. 

However, because the BMM is formally registered in the hex19 module on a mk8, it appears that the BMM uses the faster form of CAN communication protocol - so simply unplugging the connector WILL result in error message on the dash on this newer model car

Of course it's entirely your decision - however blindly making this change will very likely affect the wider-decisions for the car's Energy Management System (EMS)!!

Think about why the tweak works (if it does work at all on a mk8). The reason is because by telling hex19 module that there is no BMM, the car's EMS loses ALL the data that the BMM retrieves from the Battery. This information stream is used in part by the EMS to decide whether there is sufficient battery capacity to restart the engine after SS shuts it off when the car stops. This is why the tweak works to delete SS - because the car no longer knows the state of the battery capacity and therefor SS is disabled

BUT (yes, there is a very important "but" with this tweak) - the BMM data-stream is used by the EMS for other functions. 

This is a diagram of what's inside the BMM and what information the data-stream provides to the car's EMS - I thieved this picture from a

MQB platform car -but I expect that it is equally applicable for a MQB-evo vehicle like a mk8 (note the BMM is called J367 in the VW wiring diagrams):

As I have said, I suspect that the LIN facility in the diagram above is replaced by a pair of CAN wires on a mk8 and I expect that on this 2nd generation version of the BMM, the functions that use the battery information stream is even longer!!  However, my assumptions about a mk8 notwithstanding - what's clearly evident from the function list above is that the BMM data-stream is pivotal to a wide range of EMS decisions - extending well beyond the SS facility

I've argued in other forums that deleting the BMM data-stream from the EMS must affect the performance and longevity of the battery on cars that have SS. These EFB/AGM batteries use more sophisticated manufacturing methods than normal flooded-cell techniques  and they require more disciplined charging regimes to maximize performance and battery life. 

Notice the Shunt resistor in my diagram above - this component of the BMM measures EVERY milli-ampere of electrical current that is either drawn-from, or injected-into the battery over the life of the battery. So, together with the Battery information that the hex19 module stores as adaptation channels when the battery is installed into the car, the EMS maintains a complete history of battery capacity and it uses this historic data to adjust the optimal charging profile for maximal battery longevity! When the hex19 module is told that the BMM is not installed (via this tweak) - this entire data-stream is lost to the EMS!!

So, again it's entirely your choice - but bottom line: this tweak may well be successful in deleting SS - but I suspect that it will have other implications for the longer-term objectives of the car's EMS (IMO, of course)!

Don