Vw Passat 2012 automatic gearbox software update

[Niall]

Hello, 

Am new to the forum. Today my Passat 2012 2.0diesel automatic displayed the ignition coil symbol and lost power.

Car does not go over 40mph now and feels like the clutch is slipping.

My mechanic ran the computer on the car and picked up fault code p1741.

He told me I need be to update my gearbox software.

Can anyone shine some light on this, as I am very worried at this stage and lost for what to do.

Is this costly and who should I contact.

Many thanks niall.