MK5 Golf GTI

All Things Mk5 => Mk5 General Area => Topic started by: Mk5. EWC on March 16, 2018, 10:03:11 pm

Title: Never seen or heard fan running.
Post by: Mk5. EWC on March 16, 2018, 10:03:11 pm
I've never seen or heard the fan running on my mk5. I do motorway journeys as well as the occasional short journey but haven't heard it even in traffic. I've never had any problems with the temperature going up or any coolant problems. Any ideas?
Title: Re: Never seen or heard fan running.
Post by: acko2204 on March 18, 2018, 04:10:48 pm
Maybe check your main thermostat via VCDS when car is upto operating temp! Mine sits at 90 degrees on the dash instrument but is only registering as 74 degrees when plugged into VCDS & checked

There’s two thermostats on the manual GTi’s one’s a in-line stat & the other a main stat bolted to the block
Title: Re: Never seen or heard fan running.
Post by: Octoparrot on March 18, 2018, 04:32:58 pm
There aren't always 2 stats on manuals, mine doesn't have the inline stat just the main one. :happy2:
Title: Re: Never seen or heard fan running.
Post by: pudding on March 19, 2018, 03:59:26 pm
Put the A/C on.  You will see the fans working then, if they are working that is!

You can also test them from VCDS.  It starts them at the slowest speed and gradually works them up to full Concorde mode.
Title: Re: Never seen or heard fan running.
Post by: Mk5. EWC on March 19, 2018, 08:09:07 pm
What could be the the cause of they don't come on with the a/c?
Title: Re: Never seen or heard fan running.
Post by: bacillus on March 19, 2018, 09:04:26 pm
What could be the the cause of they don't come on with the a/c?

Make sure the fan fuse isn't blown as a starter.
Title: Re: Never seen or heard fan running.
Post by: andyiseddy02 on March 20, 2018, 06:18:20 pm
What an experience I had when I had the Passat in at a local specialist to investigate why the fans were not working.
I ended up explaining to them how it all worked. :surprised:

The car only got too hot after sitting in traffic for a LONG time, this is what confused the garage but I knew 100% that they were not working after getting stuck in the gridlocked town center, the gauge crept over 90 so I parked up and let it rest.

The thing that tells the fans to come on is built into the fan itself and is not a serviceable item, the fan must be replaced to fix it. In my case both fans needed doing as one had been running too much because the main one had failed.

When I collected the car the M60 on the way home was nose to tail so if I had listened to them I would have been stranded.

Title: Re: Never seen or heard fan running.
Post by: pudding on March 21, 2018, 12:09:31 pm
Yeah that's a good sign of the big fan failing, and also the little one can run flat out more frequently to compensate.

It's wise to periodically check the fans.  They're normally so quiet you don't notice them.
Title: Re: Never seen or heard fan running.
Post by: acko2204 on April 22, 2018, 01:34:39 pm
There aren't always 2 stats on manuals, mine doesn't have the inline stat just the main one. :happy2:

What year is your GTi ‘Octoparrot’ just out of interest
Title: Re: Never seen or heard fan running.
Post by: Octoparrot on April 22, 2018, 08:36:19 pm
It's an 06 plate.
Title: Re: Never seen or heard fan running.
Post by: mjmallia on April 23, 2018, 09:44:43 am
Mine did not work last year.

I replaced the two temp sensors and they all came back to life.
Title: Re: Never seen or heard fan running.
Post by: Mk5. EWC on June 07, 2018, 07:14:57 pm
Which fuse is for the fan? And which temp sensors did you replace? @mjmallia (http://www.mk5golfgti.co.uk/forum/index.php?action=profile;u=2133)
Title: Re: Never seen or heard fan running.
Post by: GitFlog on June 07, 2018, 07:38:52 pm
I dont know what number but when ever i check a fuse i check the whole bloody lot of them, i use my multimeter makes it so quick. a couple of times when doing this i have found other fuse that were blown.

Its just good practice if your checking a part of your car just to quickly go over everything in the area, could save you a lot of trouble in the future for 10 min checking :happy2:
Title: Re: Never seen or heard fan running.
Post by: pudding on June 08, 2018, 12:00:11 pm
S164 and S180 in the power distribution block in the engine bay, which is to the right of the battery.  Slide the cover off and you will see them.
Title: Re: Never seen or heard fan running.
Post by: Ads22 on June 11, 2018, 09:40:27 pm
Was also wondering this myself lately as to why the fans are never heard. Have one fan that works with A/C on but never with normal driving. Temp sometimes goes below 90 but never above.
Title: Re: Never seen or heard fan running.
Post by: pudding on June 15, 2018, 06:20:02 pm
You generally won't hear them unless you are sat in traffic in the height of summer with the AC set on LO.

There are a few trigger points for the fans for just engine cooling (AC off).  Stage 1 is usually around 95 degrees at a slow speed, stage 2 is around 105 and full pelt is usually around 120.  It's very rare you will hear them running fast enough to hear them in the car, except for my first sentence  :smiley:

As I say, if you have VCDS or OBD11, do an output test on the fans to confirm they are loving life and got your engine's back  :happy2:
Title: Re: Never seen or heard fan running.
Post by: Mk5. EWC on June 18, 2018, 06:37:59 pm
Which ones am I looking for? I've had a quick look over all of them and they all seem ok. What's the next step if it's not the fuses? https://ibb.co/cNJexy