Cooling fans won't shut off

diesel142

Well-known member
Joined
Apr 10, 2011
Location
st louis
TDI
2000 golf, 2015 f-350 6.7 diesel
I came out of the house today and both cooling fans where running on my 2000 golf it hadn't been started yet and it's 32 degrees outside. I pulled the plug for the temp sensor on the drivers side of the radiator but they still won't shut off. Any ideas?
 

PB_NB

Veteran Member
Joined
Nov 20, 2007
Location
Vancouver, B.C.
TDI
1999 New Beetle
I have the reverse problem, my fans wont come on at all. I think my problem is the fan control module which is probably the same problem you have. It is located under the battery or in that area. I have seen these pretty cheap online and very expensive at the dealership. You will need to get the number off the actual unit to ensure you get the right one.

Hope this helps.
 

deadend9009

Veteran Member
Joined
Jul 13, 2008
Location
Val-David, Qc
TDI
'03 Wagon
Run a search, the problem is well documented (both cases actually!)

The relay is indeed right below the battery, you need to be under the car to see it without removing anything (unless you still have a skidplate!)

If they don't work, check and see how difficult it is to turn them by hand. Mine were seized!
 

diesel142

Well-known member
Joined
Apr 10, 2011
Location
st louis
TDI
2000 golf, 2015 f-350 6.7 diesel
I just pulled the fuse on top of the battery to shut them off,I should be okay in this weather and will pull the relays under the battery to get the # Off of them and get them ordered.
 

Sky King

Veteran Member
Joined
Jun 20, 2008
Location
Pearl River, LA
TDI
2006 New Beetle DSG Trans.
Mine came back from the dealer and the fans would not shut off. Of course, the dealer said that was normal. Even 3 hours later when they were still running. :) I just disconnected the battery overnight. When I reconnected the battery they did not come back on. Of course, when my wife brought the car back to the dealer, the guy made fun and acted like he was listening for the fans, knowing they were not running. My wife responded in kind. :) A couple of months later the guy got moved to another job. He was a true idiot.
 

MrSafety

Newbie at Heart
Joined
Jun 27, 2010
Location
California... Novato... 25 Mi. N. of S.F.
TDI
2002 Jetta TDI/ALH/01M-'80 240D Mercedes/'81 Rabbit "Caddy"/'99 Lexus ES300
I suspect that the control function for one or both of these fans is actually both timer and relay...
probably both in the same component that are commonly called "fan relay" or two separate fan relays.
IF this was my DIY trouble-shoot/repair project, I would try to:
(a) determine the actual current loads there are when:
...... (1) the one fan is operating, and
...... (2) both fans are operating
(b) and then see if I could find out what the "continuous operating amperage"
rating is for the OE relay/relay(s) are.
IF these relays are not rated substantially higher than the actual amperage loads,
then this could mean the relay's power-on contacts stick closed and
then subsequently release due to cooling off or vibration!
--------------- Try this ---------
IF it stays on again... after you turn off the key and it has cooled some,
"rap" on the relay's outer case and IF the relay turns off in response,
well this is strong evidence as to what is happening!
You can purchase heavy-duty 50A, 100A & 200A industrial relays
for far less than what I suspect VW OE relays cost!
I did this to solve my repeated Glow Plug burn outs on my Mercedes 240D!
My last two 100A relays cost me less than $20/ea...
and I will be adding one of these to control
my new '81 VW Caddy P/U project car's GP system!
[IMPORTANT edit] - Keep in mind that these electrically controlled fans are
IMPORTANT in that they help to solve overheating and
damage to the aluminum heads that "percolate" when the engine is first shut down...
and the fan's continued operation is needed to reduce the
potential for warping or other damage to the weaker parts of these heads!
So don't let your zest to come up with a DIYer solution for "run-on" fans
end up costing you major engine damage!

Regards,
Sam Ross
 
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