2015 3.0tdi A4 Avant cooling fan runs full speed from cold

[mr angry]

I have an issue with a 2015 A4 quattro Avant 3.0tdi that I hope someone can help with.  The cooling fan (nearside of the two fans) will briefly spin for a couple of seconds as soon as the drivers door is opened, then stop.  When ignition is turned on or engine running, the fan will run on full speed regardless of whether car is hot or cold after been left overnight and continue running.  On turning the car off it will run for just under a minute then stop.

A scan of the car revealed fault code P0480 indicating a fault in cooling fan 1 control circuit.

I have checked the 5 amp fuse in the fusebox under the scuttle panel which I think is for the fan signal control (unsure) and it is continuous and not blown.  With the fuse removed the fan will not run when door opened or ignition on or engine running.

The EML is not on

I dont want to be just guessing and throwing parts at this so keen to hear if anyone else has experienced this or can suggest the best way forward in diagnosing.

Edited March 7, 2022 by mr angry
correction

[Stevey Y]

1 hour ago, mr angry said:

I have an issue with a 2015 A4 quattro Avant 3.0tdi that I hope someone can help with.  The cooling fan (nearside of the two fans) will briefly spin for a couple of seconds as soon as the drivers door is opened, then stop.  When ignition is turned on or engine running, the fan will run on full speed regardless of whether car is hot or cold after been left overnight and continue running.  On turning the car off it will run for just under a minute then stop.

A scan of the car revealed fault code P0480 indicating a fault in cooling fan 1 control circuit.

I have checked the 5 amp fuse in the fusebox under the scuttle panel which I think is for the fan signal control (unsure) and it is continuous and not blown.  With the fuse removed the fan will not run when door opened or ignition on or engine running.

The EML is not on

I dont want to be just guessing and throwing parts at this so keen to hear if anyone else has experienced this or can suggest the best way forward in diagnosing.

Hi its the fan control unit which Sits on the fan shroud its a silver box you can't miss it as it has cables running to each fan motor these normally go stupid at some point and are plug in and play.

Steve.

[mr angry]

This is the label for the controller but looks like it may be integral to the fan itself

[Stevey Y]

8 hours ago, mr angry said:

This is the label for the controller but looks like it may be integral to the fan itself

Hi thats not the part number thats a manufacturer number, and yes it detaches from the fan pack it is either one or two torx screws and a couple of wiring clips to each fan they do a replacement unit on line for about £70.

Steve.

[mr angry]

On 3/8/2022 at 7:28 PM, Stevey Y said:

Hi thats not the part number thats a manufacturer number, and yes it detaches from the fan pack it is either one or two torx screws and a couple of wiring clips to each fan they do a replacement unit on line for about £70.

Steve.

I have searched everywhere and was given the part number as "4H0959455AD" from a garage who want £1500 to sort it which seems a lot.  Is there any way of confirming the part number and where best to buy the controller?

[Stevey Y]

On 3/16/2022 at 6:37 PM, mr angry said:

I have searched everywhere and was given the part number as "4H0959455AD" from a garage who want £1500 to sort it which seems a lot.  Is there any way of confirming the part number and where best to buy the controller?

Hi looking at it on my parts system it does come up as a one piece unit for that part number, have a look at eBay item number 393394784912 it is not cheap but about £150 in labour it still won't come anywhere near £1500.

Steve.