citroen C4 II The cooling fan won't stop working!

[giorgostap]

Hello
For a few days now I have been facing the following problem with my 2014 C4 diesel 110
When I stop the car and turn it off, the fan runs continuously
The first time it worked until the battery died
At the workshop I took it to, they put it through diagnostics
And they decided that this was caused by low voltage since the battery was old
The battery was changed, 2 days passed without doing anything but today the same thing happened again
When I turned the car off, the fan ran continuously, forcing me to pull the plug to stop
At the workshop they found nothing again,
And they decided to change the temperature sensor
And if that doesn't work nothing, the car's brain needs to be checked
if anyone has or had a similar problem, please enlighten me because I don't know what to do
thanks in advance

[wheeler]

Any fault codes? Can they read the live data from the coolant temperature sensor?

[giorgostap]

Any fault codes? Can they read the live data from the coolant temperature sensor?

good evening
no there are no fault codes
the coolant temperature had dropped to 77 degrees Celsius and it was still working

[Paul-R]

How many times has it done that since changing the battery? If just once or twice then it's possible that the engine was trying to regenerate the DPF and was running the fans to cool the engine and DPF.

[giorgostap]

How many times has it done that since changing the battery? If just once or twice then it's possible that the engine was trying to regenerate the DPF and was running the fans to cool the engine and DPF.

it has done it 3 times
shouldn't the DPF regeneration have been done?
and it doesn't make sense to do it until the battery dies
anyway at the workshop they believe that the computer could also be at fault
because when they opened the fuse box and took out the wires one by one, only when they took out the computer did the blower stop

[PaulC5]

When you start the car does the fan come on straight away or do you only notice it when you come to stop it ? I would suspect most things on the car would stop when the computer is unplugged (assuming they mean the ecu or the bsi or the engine fuse box but it would be better to say which particular one they unplugged) so this might not be a good way to check it.

[giorgostap]

When you start the car does the fan come on straight away or do you only notice it when you come to stop it ? I would suspect most things on the car would stop when the computer is unplugged (assuming they mean the ecu or the bsi or the engine fuse box but it would be better to say which particular one they unplugged) so this might not be a good way to check it.

no, when I start the engine, it doesn't start right away
when I drove 3 kilometers and turned it off
it had already started and wouldn't stop
for at least 20 minutes with the result that I didn't want to drain my battery, I had to remove the battery terminal
when I worked on it again after doing the same route, when I stopped again, the same thing happened
maybe you're right, but I saw them do that at the garage after they first put it in the computer and they saw that it didn't show any damage or any other error or mistake

[PaulC5]

Are you putting the air con on when you use the car - just thinking if a relay may be sticking on once the fan starts up. See what happens if the air con is turned off.