Engine fan always on when engine running

[Appoman]

Hi all

Audi A6 2.0 TDi 2010 (60 plate) 

I had a service and timing belt done a few weeks back and since then the engine fan starts up immediately the engine starts and stays on until it's switched off. No over-run, that I've noticed.

Audi told me that the DPF sensor had a fault and was causing the problem. Got the job done, collected the car and guess what - the fan is still on all the time. Sods must have known it wasn't fixed. I'll be taking it back, but in the meantime does anyone know if there is anything that could have been damaged during the timing belt work which could be the cause? Call me suspicious, but this problem only started immediately after the timing belt work was done....

I'm not a massively experienced car mechanic, most knowledge is to do with 2002 BMW 530i M Sport, but I am reasonably practical and if there are coolant temperature sensors (for example) which I can check then please can someone point me in the right direction or give me a link to previous threads if they deal with this issue? The coolant level seems too high in the reservoir, don't know if that can cause an issue?

cheers

Appoman

[Jonny1971]

I have A6 2.0 tdi 2010 have same problem engine fan runs whilst engine on but engine not getting hot have had fan control module changed but still have the problem not sure wht to do ?

[Appoman]

Hi Jon

Nobody replied to my post with a solution, but I may now be able to help you instead 

The fault was not the DPF sensor, but it was the aircon pressure sensor - replaced that, and all is good.

I was only billed for one job too, so have to applaud Audi for that

Hope it helps

Steve

[Jonny1971]

Thanks Steve will look into that many thanks mate 👍Jon 

[Appoman]

no problem, that's what these forums are all about :-)

[Magnet]

Hello Jon, 

When you say the engine is not getting hot, do you mean not overheating, or not getting up to temperature? if its not getting up to temperature then it would be wise to have the actual running temperature measured. 

For both,

Sensors such as the coolant temperature sensor can cause the fan to run all the time if they become faulty or go open circuit, since the system goes into fail-safe and runs the fan as it would do if it was running over temperature.

Kind regards,

Gareth.

[Jonny1971]

Hi sorry I meant engine not over heating and is running at correct temp 👍

[Guest BMW_Mania]

On 2/14/2018 at 7:38 PM, Appoman said:

Hi Jon

Nobody replied to my post with a solution, but I may now be able to help you instead 

The fault was not the DPF sensor, but it was the aircon pressure sensor - replaced that, and all is good.

I was only billed for one job too, so have to applaud Audi for that

Hope it helps

Steve

Thank you so much Steve 🙂

[Dave ex]

So I've been through the same thing the engine runs the fan constant until the engine shuts of I've had the dpf cleaned  the fan control module replaced and fan switches replaced nothing has sorted it but my local independent garage has been looking into the software's and discovered that there is a software setting that says engine cooling and gives the option single fan and twin and they are set to constant..the main dealership  did not even know about this and just charges and a little garage workout it's in the software settings

[Danny wood]

I have changed the ac pressure sensor and my fan still kicks in as soon as the engine has started I have booked it in for a regas as I don’t think my ac is working ether not Ice cold I’ve read up that if you have no gas but you have changed the sensor it will still be in error has anybody had to do this to get the fan to stop kicking in straight away a6 avant 2.0d 2010 

[Danny wood]

I have changed the ac pressure sensor but the fan still kicks in soon as I start the car and the fault still comes up when it gets plugged in am I right that the fault will stay if there is no gas in the ac ?? Thanks 

[Danny wood]

On 2/23/2021 at 1:24 AM, Danny wood said:

I have changed the ac pressure sensor and my fan still kicks in as soon as the engine has started I have booked it in for a regas as I don’t think my ac is working ether not Ice cold I’ve read up that if you have no gas but you have changed the sensor it will still be in error has anybody had to do this to get the fan to stop kicking in straight away a6 avant 2.0d 2010 

 

[Laisor]

On 2/14/2018 at 12:42 PM, Jonny1971 said:

I have A6 2.0 tdi 2010 have same problem engine fan runs whilst engine on but engine not getting hot have had fan control module changed but still have the problem not sure wht to do ?

 

[Audi Andy.]

On 7/9/2019 at 8:13 AM, Guest BMW_Mania said:

Thank you so much Steve 🙂

Thank you very much. Having this same issue currently in Sept 22 with my 2010 C6 Avant Le Mans S line 2.0 TDI.  so this is good to know. I also have the headlights that like to flicker on and off randomly, anyone experienced this phenomenon?

Andy