Audi a4 fan running when engine is off

[Tuseefahmed27]

Hi I have recently bought an audi a4 2.0 diesal 57 plate. Since buying the car once in a while when we switch of the engine the fan starts to spin. I have bought a replacement fan control module and fan and it does the same on that so I have returned it back to the seller. I've already had a flat battery once and I'm afraid it will happen again. Sometime if you turn the ignition and then lock the doors it doesn't spin it's hit and miss.

[JDillon15]

I think that's a symptom of your thermostat is bad? Could be wrong, but that's a place to look.

[Theiceman]

I think it is wired that the fan will come on regardless of ignition status if it detects engine temp too high
Thermostat is definitely a possibility but I would put vag com on their and monitor engine coolant temp. if it is way out of whack it could be your engine coolant temp sensor. I don't know that engine and if there are separate sensors for the guage and fan switch however.

[Tuseefahmed27]

Thankyou all I'm taking it back to the dealer next week. I'll see what he says.

[adam044]

I think all cars do that sometimes. Does it turn off after a few min? Are you in a hot climate?

[Schweini]

Thermostat

[esandes]

I think it is wired that the fan will come on regardless of ignition status if it detects engine temp too high
Thermostat is definitely a possibility but I would put vag com on their and monitor engine coolant temp. if it is way out of whack it could be your engine coolant temp sensor. I don't know that engine and if there are separate sensors for the guage and fan switch however.

I think all cars do that sometimes. Does it turn off after a few min? Are you in a hot climate?

i agree. there's nothing wrong with it. my old VW did it all the time. my audi doesn't get too hot very much.

[brandonpham]

Mine was Engine Coolant Temp sensor. That solved it for me. The one by the firewall on the coolant flange.

[Tuseefahmed27]

No it can go on for a long time that's what I initially thought

[Tuseefahmed27]

Mine was Engine Coolant Temp sensor. That solved it for me. The one by the firewall on the coolant flange.

I thought it could be that. Apparently it can't be seen on the a4 diesal you can feel it if you put your hand down the back of the engine

[Tuseefahmed27]

I think all cars do that sometimes. Does it turn off after a few min? Are you in a hot climate?

No I'm in the uk

[Tuseefahmed27]

Dropped it off at the dealers this morning amd just rang him they have had to order a new module from audi and fit it in. Ouch that's going to cost a lot.