2.0 170 S-line Fan running all the time

**Islandboay** · 12-01-2015,08:31 AM

Turned out to be a faulty AC pressure/Temp sensor. Sensor -G395 IIRC. The one on the condeser.

Thanks for the help regardless.

**Jethro48** · 12-01-2015,03:00 PM

Glad you got it sorted, can be a real pain!

**Pilotechy** · 27-02-2017,07:14 PM

Originally Posted by Islandboay

Turned out to be a faulty AC pressure/Temp sensor. Sensor -G395 IIRC. The one on the condeser.

Thanks for the help regardless.

Hi, I know this was a while ago but mine is doing the same. How did you narrow it down? Did it show up as faulty in the VAGCOM scan?
Thanks

**supernoodle** · 13-03-2017,02:35 PM

I've got the same error on my car. Yes the error shows up in VCDS (00256). I also notice when you you look in advanced measuring values under engine you can pull some very useful measurements, like Fan1_rPs, Fan2_rPS and several other Fan_rClgDemXXX labels. These show what feature is demanding the cooling fans and at what duty cycle. On mine the one with AC in the name shows a 100% demand request and I have Fan1_rPs of 89.9%. So with a 00256 error and an AC fan demand, pretty clear that's the culprit.

I'm doing this from memory as I don't have my VCDS session to hand. I'll check when I get the logs to hand.

**Trickz8** · 16-03-2017,03:45 AM

Hi,I had same problem on my 2.0 tdi got a new ac pressure/temp sensor two days ago fitted within 30mins only have to pull bumper out on near side slightly to access switch,hope you guys got it sorted ��

**supernoodle** · 16-03-2017,01:46 PM

Found a screen capture I took from VCDS. The FanCtl_r_ClgDemAC_mp was 100% regardless of AC being on or off. AirC_p_CInt (the AC refrigerant pressure), was 65534 which is effectively maximum, ie implausible. This correlated with the 00256 - A/C Pressure/Temperature Sensor (G395) fault I had. All pointed to a duff sensor. Sensor replaced, all OK now.

VCDS_Fans.jpg

**Pilotechy** · 21-03-2017,08:10 AM

Thats great, Thank you. I got a scan and indeed came up with a fault on the G395 sensor with the 00256 fault code... Although it says sporadic so will check the connector first as it looks a pain to change..

**Sambor11** · 28-11-2017,09:55 PM

Hi everyone! I just notice tonight that my cooling fun is running constantly as soon as I turn on engine and stops when I turn off engine! A6 2.0 tdi March 2011 model 2010) 170 bhp. Does somebody knows what can cause this problem and if I can drive to work about 25 miles? Is any recals for it?
Thank you for any suggestions!!!

**supernoodle** · 28-11-2017,10:18 PM

Sambor11, you really could do with getting a scan for any codes. If you can get VCDS look for the labels in the screenshot I posted, that's the real clincher.
It's more than likely the AC pressure sensor, the fact that the dealer had 30 in stock is an indication of how common the problem is, but no recalls I'm aware of.
I drove for a good few months with the problem on mine before I fixed it, no ill effects.
I forget the exact price, but parts ( sensor and seal) were about £60. It's easy to change, just some sockets and screwdrivers is all you need.

**Sambor11** · 28-11-2017,11:17 PM

Originally Posted by supernoodle

Sambor11, you really could do with getting a scan for any codes. If you can get VCDS look for the labels in the screenshot I posted, that's the real clincher.
It's more than likely the AC pressure sensor, the fact that the dealer had 30 in stock is an indication of how common the problem is, but no recalls I'm aware of.
I drove for a good few months with the problem on mine before I fixed it, no ill effects.
I forget the exact price, but parts ( sensor and seal) were about £60. It's easy to change, just some sockets and screwdrivers is all you need.

Thank you for your replay! Can you tell me where is located this sensor?