I've had this car for 4 years and this problem has appeared every now and then but currently very persistent.

Sometimes the slightest touch on the washer/wiper stalk without even switching anything is enough to send the washer crazy and sometimes very hard to switch off again. Have even seen it caused by a bumpy road or sharp corner. There are no relevant faults showing on VCDS. The way it is behaving suggests to me that it is an intermittent connection or switch contact problem in that area. Has anyone seen anything similar or can suggest anything.

My inclination is to try changing the Steering Column combi switch. However I'm having trouble deciding on what part number to look for as there seem to be about 50 possibilities for this VIN and PR combination. Best guesses so far are 4N0907129 AB or HD or MQ but really not sure. Hoping Crasher might be able to help with this (again!). VIN is WAUZZZF48HA011388.

And a connected question: I believe that this switch assembly contains a control module - but does a replacement require coding?

Thanks in advance