Fan not kicking + A/C stopped working

[psytcp]

I ve got a 2004 MK5 golf TDI 2.0 and when I bought it a while ago the small fan was not working at all; Large fan was working almost constantly at full speed and AC was fine.

A couple of days ago I tried to operate the A/C and it wont blow cold air at all, however if turned to hot it works fine. I also realised that the big fan is not working anymore! So none of the fans will go on if the engine is warm or if you turn on the ac.

I did an auto scan through Vag Com but didnt get any faults, I then tested the Cooling fan 1 output and it worked; the fan started spinning like normal, so I guess the fan motor itself is working. Another thing worth mentioning is that the Temperature gauge hasnt gone above 90 degrees even after driving for more than an hour on motorway or minor traffic jam.

I dont want to take my car to stealers which will ask me to leave it with them and charge me silly money. I d rather try some things DIY and replace the part myself if possible or just go to some garage with a problem.

To summarize:
-Small fan is not working at all; Havent tried to measure voltage to it.
-Large fan is not kicking in at all; Was tested through vagcom for operability and worked fine
-A/C not blowing any cold air at all, when turned to hot it blows hot fine; Refrigerant pressure meassured with vagcom ~5.2 bar.

I dont mind fixing the AC at this point, Im more concerned about not frying the engine.
Any input would be highly appreciated! :bow:

 

[psytcp]

noone?

 

[nitroscope8]

Replace the small fan first. You are killing the large fan by making it work overtime. The large fan is the module and controls the small one so if the large one works the small one should.

Using vagcom, check the value blocks in the AC electrics with the ac on full. Check the "compressor off code" and see why the compressor is NOT turning on. This will answer your AC problem. The pressure in your ac system is normal pressure without the pump working.

 

[psytcp]

I understand that I need to replace the smaller fan but why is the larger fan not kicking for cooling the engine? apart from the A/C issues.

I am really tight on budget at the moment so I would prefer to find a fix for the larger fan as a temporary solution just to be safe, and will shortly after replace the small one.

Since I haven't checked the working condition of the small one, I don't want to replace it right away as the problem might be elsewhere and not allowing both fans to kick?

Also, the compressor off code was set to 0 which means that the compressor was operating. Refrigerant pressure 6.6 when on if it matters.

Still no fault codes whatsoever.

 

[psytcp]

bump

 

[psytcp]

Does that 0 indication regarding the compressor really means that the compressor is working?

If so, then it has to be some cooling module that is faulty right? Which doesn't allow the fan to kick in.
thanks

 

[fastwire]

my fans doesnt move. only the smaller at full when AC is on. is that normal?

 

[The Fed]

90c or f?

 

[fastwire]

wat

 

[The Fed]

my fans doesnt move. only the smaller at full when AC is on. is that normal?

No. The large fan should also run. Sit at idle. It should kick in after the car heats up.

 

[The Fed]

bump

The controller for at least the small fan is in the large fan and is not sold separately. You can try seeing if the small fan runs when voltage is applied to it but without a properly working controller it won't kick in. The small fan runs when the AC is on.

If the small fan is truly burned out you need a small fan. If you replace the small fan and it still doesn't run correctly, or the large fan still runs excessively, you also need a large fan, since the controller like I said isn't replaceable.

That your AC compressor is not running could be caused by a number of things. You could be low on refrigerant, your pressure switch could be bad (I don't know if our system has both low and high or just low), your evaporator temperature sensor could be bad, or you could have a bad compressor. And there's always the possibility the dash switch or module or wiring could be bad, or you blew a fuse.

Before you start spending who know how much to indiscriminately replace parts, let a trusted dealer, if there is such a thing, diagnose it for you. Get the fans operating correctly then look at the AC.

I had the same fan problem and the dealer needed to replace both fans. It was under warranty. A few months later my AC was taking 10 minutes to kick in. Car was still under warranty. They replaced the evap sensor with no joy. Since that didn't fix it they replaced the compressor and receiver/dryer. All was good then. Cost if I needed to pay for it all would have been I figure $3,000.

There's a temp sensor for the coolant temp but I don't know where it's located. I think VCDS should have picked it up if it were bad. You might want to email Ross-Tech if you're a registered user to see if the engine scan checks for it.

 

[fastwire]

No. The large fan should also run. Sit at idle. It should kick in after the car heats up.

ok thanks for the reply.

no it doesnt kick in never, Ive been driving trough slow traffic, and then stop, open the hood and both fans dead.

Yesterday at the highway the temp gauge went dead, but I think is because of the weak thermostat.

Only fan activity is when I turn on the AC, it will kick the smaller fan at full blast making it sound loud.

Any recommendation on what to do?

As the small fan turns at full with the AC, then I need to replace the bigger fan only?

 

[The Fed]

Our fans are I believe 2-speed so I would say replace the large fan.

 

[fastwire]

Our fans are I believe 2-speed so I would say replace the large fan.

thx. yeah I think the same. gonna try testing the fans with vagcom 1st though.

 

[The Fed]

There's a VCDS test for them? Heck, even the dealer did the, "let's try replacing the small fan and see what happens", and it was under warranty, where they need to turn in the old parts to VW.