Why does the cooling fan have to go on when the engine is off?

During a regen the DPF heats up to 800C. This is why the fan must go on whether the car is running or not. Don’t try to stop it by turning off the car and then back on, this only defeats the purpose. Let the car do what it does as this is how the computer is programmed. All is well in CTD land.

Why does my Jetta not have a cooling fan?

Simply the engine is not hot enough to turn on the cooling fan, its not hot enough outside, you are driving getting plenty of air flow through the grille to keep things cool without the assistance of the fan. Its possible that you have no problem at all. Was this answer helpful? I got a 2002 Jetta the cooling fans don’t turn on .

Are there any problems with the radiator fan?

Yes, at least for me. Once the PCM was replaced and reflashed, along with the other work, the problems with the radiator fan have gone. I have been fine ever since.

Why are the fans not working on my Chevy truck?

He cleared the codes, which ended up being a knock sensor code. After this procedure, everything had been working fine. About a day or two later the check engine light reappeared. I monitored the truck for the fan problem, the fans never came back on. I already had an appointment for my 100k service so I waited.

What are the signs of a bad cooling fan?

Common signs include the engine running hot and cooling fans either not functioning or running all the time. 1. Engine running hot 2. Cooling fans do not function 3. Cooling fans stay on at all times Most modern vehicles use electric cooling fans to help pull air through the radiator so that it can keep the engine cool.

Why are my cooling fans running at all times?

3. Cooling fans stay on at all times. If the cooling fans are staying on at all times, this is another (less common) symptom of a possible problem with the cooling fan relay. If the relay shorts internally, it may cause power to be permanently switched on, which will cause the fans to run at all times.

How often does a car cooling fan stay on?

Cooling fans stay on at all times Average rating from 129,472 customers who received a Vehicle Engine Cooling Inspection. Most modern vehicles use electric cooling fans to help pull air through the radiator so that it can keep the engine cool.

Why are both radiator fans running at the same time?

In prepping for a 2K trip next week, there couple of quibbles I need to address. Both cooling fans run constantly. The AC is off. Engine cold, start up, and they both run continuously. Key off, and they both stop.