A late update:
About a year ago the problem was finally solved. A mechanic from Lloyd Newcastle BMW claimed that there was a short circuit and the main unit had to be replaced.
I ended up leaving my car several times at Lloyd Newcastle BMW. They diagnosed the fault as caused by short circuit. They recommended replacing main unit module. That helped.
Thanks guys for some suggestions. I found a thread describing two ways of cleaning the clogged washer jet system:
http://f30.bimmerpost.com/forums/showthread.php?t=1235500.
I did not want to remove the pump so I decided to choose second method:
My car has got ceramic coating protection but I...
First of all, hello everyone! This is my first post here. I was advised about using this forum by a person driving Z4 I met while having a stop for a coffee on my Newcastle upon Tyne to London trip by my Z4 :D
Occasionally, windscreen jets stops spraying a liquid. Wipers work at that time and...