[damtom85]

ok let me sum up,

my engine is 3.0 tdi. according to audi in my car is only one valve- n509 doesn't exist in 3.0tdi, only n488 and has number 4H0121671D and looks like that:
https://flic.kr/p/HPEtKN

and in my case this valve is located next to gearbox, between gearbox and geabox heat exchanger (small radiator)

also circulation pump v50 has number 059121012A and looks like that https://flic.kr/p/JKX8Va

and it is located in firewall on left side if you look from front of the car
https://flic.kr/p/JKWJdF

https://flic.kr/p/JKWJbr

https://flic.kr/p/Jkam8C

and this error / fault

Address 08: Auto HVAC (J255)       Labels: Redir Fail!
   Part No SW: 4H0 820 043 G    HW: 4H0 820 043 G
   Component: Klima 2 Zonen H20 0110  
   Coding: 3621002830
   Shop #: WSC 02313 785 00200
   ASAM Dataset: EV_AirCondiFront 001050
   ROD: EV_AirCondiFront_AU64.rod
   VCID: 2447AAB92FD469012A7-8071

1 Fault Found:
0378 - Coolant Circulation Pump 
          B10D0 04 [009] - Internal System Fault
          Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 3
                    Fault Frequency: 1
                    Reset counter: 114
                    Mileage: 79318 km
                    Date: 2015.03.27
                    Time: 08:02:51

it is caused by this pump, and needs to be replaced for error to be gone.

thanks