Testing radiator fans

07ktm250xc

Well-known member
Joined
Dec 18, 2011
Location
West Virginia
TDI
2014 Jetta TDI DSG
Bought a 2006 Jetta 1.9 yesterday...having issue with fans not coming on.
Heres what I think so far...

There are 4 wires at the plug to the fans. 2 are small and
2 are large.

There are the two large wires ( one red the other orange). Is that
where I check power to the fans?

I have the a/c on and there is no power at either the red or orange.
The a/c discharge pressure is above 200# also.

Thanks for any advice.
 

rjsummer

Well-known member
Joined
Mar 29, 2006
Location
Kitchener Ontario Canada
TDI
Gray 2003 TDi GLS 5spd Sunroof
My Bentley manual says for a 2 speeds with thermal switch, that the brown at T4/4 is ground. T4/1 is Red and gets power directly from Fuse 3 on fuse panel A, 50 amps. Small black wire at T4/2 comes from fuse 24 on fuse panel B, 10 amps. The last wire at T4/3, green, comes from the ECU. On all cars but engine code BRM, it connects to the ECU at pin 66. ( think that's all gas cars?) If you have a BRM engine code, it comes from pin 47. If you need any more info I'll be happy to look it up.

Fuse panel A is in the left rear engine compartment, on the side of the box.
Panel B is under the plastic cover on top of the box.
 

07ktm250xc

Well-known member
Joined
Dec 18, 2011
Location
West Virginia
TDI
2014 Jetta TDI DSG
Thanks rjsummer

50a fuse was blown..put in a new fuse and now the large
fan won't stop running. Even after turning off the key
and letting it sit for 5 minutes.

also, there is a steering wheel and traction control light on now
that won't shut off.

any other suggestions?
 
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07ktm250xc

Well-known member
Joined
Dec 18, 2011
Location
West Virginia
TDI
2014 Jetta TDI DSG
Well..after further research..

Could it be that the control module in the large fan is toast?

Also, read something about it possibly being the radiator sensor?

Any other suggestions?
 

Ludicrous Speed TDI CUP

Veteran Member
Joined
May 4, 2012
Location
Northern IN
TDI
2010 TDI Cup, 06 Jetta TDI
Had this exact problem... Yesterday as a matter of fact.

I called VW... If you have "Semmens" Brand fans... You have to replace both. :(

If you have Bro brand I think that's what he called it.. you can replace just one.

I had the Semmens so at over 250.00 a fan my cost I decided to just put a

set of Spal fans (Off my Camaro race car) on the Jetta. They out flow the

stock fans and I did my own relay setup. The Red wire is Hot at all times.

The brownish wire is ground. (The two smaller wires are how it knows when A/C is on

and Temp is hot.

I had the steering wheel light come on sometimes but not sure what's up with that????

Hope that helps,
Scott~
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
There is an updated cooling fan for those cars. They are not all that expensive, very common issue. I know the little one is only $65 or so. The bigger one is more, but it also contains the control module.
 

07ktm250xc

Well-known member
Joined
Dec 18, 2011
Location
West Virginia
TDI
2014 Jetta TDI DSG
Thanks guys

Ordered two fans..$250 shipped. Thought it was kind of high but they
were the cheapest fans I could find that weren't the chinese stuff. Supposed
to be OEM without the VW label..well..we'll see. <smile>

Thanks Ludicruos..we just put a swithch on it for now so we could drive it
with at least one fan running. I too was thinking about installing our own
relay/temp sensor setup when we found out what the dealer wanted for the fans.
I just might have to pm you if we change our minds or the fans we bought
go out again. Do you know if the small a/c wires are just a switch from the
refrigerant discharge line? If so I would assume they should be open until
the discharge pressure gets high enough to turn on the fans?

Thanks oilhammer..where did you find the small fan for $65 ?

edit..oh..btw.. the steering wheel light should go out after a while. You probably disconnected
your battery. Found that out researching this site. :D
 
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rjsummer

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Joined
Mar 29, 2006
Location
Kitchener Ontario Canada
TDI
Gray 2003 TDi GLS 5spd Sunroof
I only have an 06 Jetta 2.5 DSG, and I haven't done a lot to it, but like I said I have the Bentley manual so if you need any pages sent in an email just ask and Ill use my iphone to send em. Any idea how to get forum messages or responses to alert me by email? I cant figure it out.
 

07ktm250xc

Well-known member
Joined
Dec 18, 2011
Location
West Virginia
TDI
2014 Jetta TDI DSG
I only have an 06 Jetta 2.5 DSG, and I haven't done a lot to it, but like I said I have the Bentley manual so if you need any pages sent in an email just ask and Ill use my iphone to send em. Any idea how to get forum messages or responses to alert me by email? I cant figure it out.
If you go to private messages then go to edit options you should be able to change it there. Thanks for the help, hopefully we will get it fixed tomorrow when the fans come in.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
Thanks oilhammer..where did you find the small fan for $65 ?
I think 1stvwparts has them for that. The LIST price from Volkswagen is only $80 for the small (295mm) fan, the newer part number.

The big fan (360mm, with the module) is still about $260 list. Which, to be fair, is cheaper than the old cars' big fan and module combined, so....

1K0-959-455-EA (360mm)
1K0-959-455-ES (295mm)
 

07ktm250xc

Well-known member
Joined
Dec 18, 2011
Location
West Virginia
TDI
2014 Jetta TDI DSG
Thanks again guys

Got the new fans in and everything works. <smile>

Tested the old small fan and it ran but since it was out I went ahead and installed the new one. Since both of the old motors worked..my guess is it was the control module.

Wish we could have just bought that part..must be a rea$on why we can't. LOL

Would still like to know if the two small wires are inputs/outputs/contacts and
what they control or sense.

The repair was very easy..Disconnect plug, 4 screws holding the shroud and remove from the bottom. A little prying was required but nothing that would break anything.
I removed an air filter intake boot for better access to one of the top screws..thats
about it.
 
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oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
I believe the two small wires are the paired data signal wires to the module, which talks to the Climatronic or Climatic (depending on which version HVAC the car has) module as well as the Engine Control module. It is a FAR simpler setup that the A4 and A3 cars had, with their giant external module with either 10 or 14 pin connectors as well as the high voltage connector. Unfortunately, it isn't any more durable it would seem. :(
 

Andrewh

Veteran Member
Joined
Aug 1, 2006
Location
Allen, TX
I have not verfied this, but the connector is very simlar to the mercedes fans I played with on an older (1965) car. Fans were from 2008-20012 mercede's.

the two big wires are power and ground.
the 2 smaller ones are controls for the fan.
1 of them wired directly to power turns the fan on full speed.
the other needs some regulation and controls the fan speed.
on the mercedes it is a pulse so you can direct the fan from 25 percent to 100 percent.
A guy built an aftermarket controler for them, and I was testing them out.
 

07ktm250xc

Well-known member
Joined
Dec 18, 2011
Location
West Virginia
TDI
2014 Jetta TDI DSG
I believe the two small wires are the paired data signal wires to the module, which talks to the Climatronic or Climatic (depending on which version HVAC the car has) module as well as the Engine Control module. It is a FAR simpler setup that the A4 and A3 cars had, with their giant external module with either 10 or 14 pin connectors as well as the high voltage connector. Unfortunately, it isn't any more durable it would seem. :(
So basically..they are communication wires from the ecu/climatronic? And we can only see their fuction and operation with a vagcom?


Thanks oilhammer for the reply and all your help..:D
 
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07ktm250xc

Well-known member
Joined
Dec 18, 2011
Location
West Virginia
TDI
2014 Jetta TDI DSG
I have not verfied this, but the connector is very simlar to the mercedes fans I played with on an older (1965) car. Fans were from 2008-20012 mercede's.

the two big wires are power and ground.
the 2 smaller ones are controls for the fan.
1 of them wired directly to power turns the fan on full speed.
the other needs some regulation and controls the fan speed.
on the mercedes it is a pulse so you can direct the fan from 25 percent to 100 percent.
A guy built an aftermarket controler for them, and I was testing them out.

Thank You..seems a guy would need the vagcom to know what is
supposed to happen under certian conditions.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
So basically..they are communication wires from the ecu/climatronic? And we can only see their fuction and operation with a vagcom?


Thanks oilhammer for the reply and all your help..:D
The Fan module doesn't have its own accessibly address via scan tool, but you can access the other modules that do. Kind of like the door modules... you can only "see" them through the Central Convenience or Electronics module, not directly.
 

07ktm250xc

Well-known member
Joined
Dec 18, 2011
Location
West Virginia
TDI
2014 Jetta TDI DSG
Thanks again oilhammer..seems every question you answer for us generates
another question..lol

Is "scan tool" a program in the vagcom or a separate device?

Feel free to tell me to just go away..<smile>

Either way..Thanks for everything..the car works great.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
When we say "scan tool", we mean anything that accesses the various modules of the car via the DLC (Data Link Connector). In the case of VCDS (formerly known as "VAG-COM"), it is a scan tool that runs on a PC and connects via ross-tech's proprietary cable through the USB port or (on older versions) a serial port.

VCDS is a VAG-specific scan tool, in that it 'speaks' the same language that the car does, and connects to it using the same protocols as the scan tools the dealers use. So it works great, is fast, reliable, and gives full access to each and every module on the car, and there can be quite a few, especially on some of the fancier models like the Phaeton, A8, T'reg, etc. It doesn't rely on the dumbed-down, truncated generic "OBD2" side of things, like those lame cheapo hand-held jobs Autozone and others will try. There are VAG-specific hand-held scan tools like those out there, but they typically cost just as much if not more than VCDS and don't seem to be as user-friendly, not to mention they don't have the extra spiffs like long coding helpers, etc. Not to mention ross-tech has excellent tech support. Any time I have emailed them, someone has gotten back to me usually within an hour, and has always been able to help me with whatever issue I was having.
 

gquenstedt

Veteran Member
Joined
May 26, 2006
Location
San Antonio, TX
TDI
'06, '03 x 2, '00
I think 1stvwparts has them for that. The LIST price from Volkswagen is only $80 for the small (295mm) fan, the newer part number.
The big fan (360mm, with the module) is still about $260 list. Which, to be fair, is cheaper than the old cars' big fan and module combined, so....
1K0-959-455-EA (360mm)
1K0-959-455-ES (295mm)
List on 1K0-959-455-ES shows to be $292

I found 1KM-959-455-D list $86, but that shows to be for the newer '12 cars. Will it work on the '06 BRM?
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
There are two fans for BRM cars, the early and the late. The early supercedes to the late (which is what the newer cars would already have). It is an improved fan, but I think before too long we'll start seeing a bunch of those failing too, given how much the newer cars tax the fans. I've already replaced a couple on CBEA cars.

But hey, they all fail eventually, and the Ford Edge yesterday Joe had in here sucked a whopping $750 out of its owner's wallet to replace the fans, so....
 
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