I've had my 530D 2010 recently diagnosed and it appears that the Preheating Control Unit is not operating (No Voltage) causing shaky engine on cold start.

I've received quotes for replacing and fitting the part from Independent BMW approved garages and my local dealer. The cost of the part is 106+VAT - supplied from BMW. The labour cost ranged from 75-90.

However only the local dealer (Service department) suggests that I need a software update after the component is fitted. This will take approximately 2.5hrs costing an additional 300. To get this even more confusing - I spoke to the Parts department at the same local dealer (to get the parts quote) and the technician in that department confirms that the software update is not required. The independent garages did not mention anything about software update either.

So my question is, after replacing this Preheating Control Unit (I believe it's responsible for operating the Glow Plugs) do I need a software update or is it an option?

Has anyone had this replaced on their cars? - any help/advice on this would be appreciated.

Many thanks