AudiForums.com

Go Back   AudiForums.com > Audi Tech > General Tech
Sign in using an external account
Register Forgot Password?
Search

General Tech
Good at troubleshooting? Have a non specific issue? Discuss general tech topics here.

Welcome to Audi Forums!
Welcome to Audi Forums,

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!


Reply
 
 
 
 
LinkBack Thread Tools Search this Thread
  #1  
Old 04-25-2009, 08:14 PM
SloRide's Avatar
1st Gear
 
Join Date: May 2006
Posts: 140
Points: 6,373, Level: 52
Points: 6,373, Level: 52 Points: 6,373, Level: 52 Points: 6,373, Level: 52
Level up: 12%, 177 Points needed
Level up: 12% Level up: 12% Level up: 12%
Daily Activity: 0%
Daily Activity: 0% Daily Activity: 0% Daily Activity: 0%
Default Radiator fans not working

Neither fan is working on my 96 2.8l A6. I searched the forums for similar problems and so far this is what I have checked.
1. Fan temp switch on the radiator (when the motor was hot i had continunity on all 3 terminals). Measured 12v on 2 of the 3 terminals of the connector and jumpering to the 3rd did nothing.
2. checked the 2 fan relays in the plenum box. pulled them out and hooked up 12v to each coil (to make it switch) and had continunity on the other terminals. They seem fine.
3. I noticed that the scockets for the relays had 12v on the terminals that fire the coils, but the terminals that get switched thru the relay did not have 12v on any side of the switched terminals (#30 and #87). I might be looking in the wrong direction but i think there should be 12v on one of those terminals.
4. I looked under the drivers side dash/knee board area and found more 6 more relays, but none of them were labled for the fans.
5. Checked the fuse panel and did not find any problem there.
6. Cut the wires to the fan and put 12v from a seperate battery and it worked.
Could there possibly be a fuse somewhere that I'm missing? It seems like i'm not getting 12v to the relays in step 3.
Any thought?
Thanks
  #2  
Old 04-25-2009, 09:57 PM
Jackmup's Avatar
2nd Gear
 
Join Date: Mar 2009
Location: New York
Posts: 1,227
Points: 7,872, Level: 59
Points: 7,872, Level: 59 Points: 7,872, Level: 59 Points: 7,872, Level: 59
Level up: 61%, 78 Points needed
Level up: 61% Level up: 61% Level up: 61%
Daily Activity: 26.5%
Daily Activity: 26.5% Daily Activity: 26.5% Daily Activity: 26.5%
Default

Has it thrown any codes? checked your temp sensor?
__________________
02-A6 Quattro 3.0 Avant
00-A8 Quattro 4.2
  #3  
Old 04-26-2009, 06:05 PM
SloRide's Avatar
1st Gear
 
Join Date: May 2006
Posts: 140
Points: 6,373, Level: 52
Points: 6,373, Level: 52 Points: 6,373, Level: 52 Points: 6,373, Level: 52
Level up: 12%, 177 Points needed
Level up: 12% Level up: 12% Level up: 12%
Daily Activity: 0%
Daily Activity: 0% Daily Activity: 0% Daily Activity: 0%
Default

The temperature gauge seems to be ok. starting from cold the needle moves to a normal position as the engine warms up, so i'm quessing the sensor is working. my a/c unit can double as a diaognostic display and is showing the folowing DTC codes.
"15.3 - Air Flow Flap Motor Potentiometer, sporadic open" and "22.3 A/C Refrigerant High Pressure Switch, sporadic open" and I'm not sure what they mean or if they are part of the problem. The a/c blows cold air too.
__________________
Earth First! We'll ride the other planets later.
  #4  
Old 04-26-2009, 09:58 PM
Midniteoyl's Avatar
4th Gear

 
Join Date: Mar 2009
Location: Indiana
Posts: 3,041
Points: 6,139, Level: 50
Points: 6,139, Level: 50 Points: 6,139, Level: 50 Points: 6,139, Level: 50
Level up: 95%, 11 Points needed
Level up: 95% Level up: 95% Level up: 95%
Daily Activity: 3.6%
Daily Activity: 3.6% Daily Activity: 3.6% Daily Activity: 3.6%
Default

Those codes are for the climate control...

Anyways, somewhere between the fan relays ans the fans themselves there is an open (as you know). I dont have the diagram so cant point you to where its at, but this problem and the climate control ones point me to either a loose connector or open wires, prolly due to them rubbing metal. Find the power wire at the fans and follow them back. Found a 'bad' fuel pump and 'bad' transmission this way, both actually due to broken wires.

Second possibility is a fuseable link somewhere in line.
__________________
Jim

'96 A6Q - 180+K miles
  #5  
Old 04-26-2009, 10:45 PM
Midniteoyl's Avatar
4th Gear

 
Join Date: Mar 2009
Location: Indiana
Posts: 3,041
Points: 6,139, Level: 50
Points: 6,139, Level: 50 Points: 6,139, Level: 50 Points: 6,139, Level: 50
Level up: 95%, 11 Points needed
Level up: 95% Level up: 95% Level up: 95%
Daily Activity: 3.6%
Daily Activity: 3.6% Daily Activity: 3.6% Daily Activity: 3.6%
Default

heres the wiring diagram

lets try this again.. PDF due to size

Attachment 3140
Attached Files
File Type: zip a6 rad fan.zip (59.9 KB, 128 views)
__________________
Jim

'96 A6Q - 180+K miles

Last edited by Midniteoyl; 04-26-2009 at 11:28 PM.
  #6  
Old 04-26-2009, 10:46 PM
Midniteoyl's Avatar
4th Gear

 
Join Date: Mar 2009
Location: Indiana
Posts: 3,041
Points: 6,139, Level: 50
Points: 6,139, Level: 50 Points: 6,139, Level: 50 Points: 6,139, Level: 50
Level up: 95%, 11 Points needed
Level up: 95% Level up: 95% Level up: 95%
Daily Activity: 3.6%
Daily Activity: 3.6% Daily Activity: 3.6% Daily Activity: 3.6%
Default

fixed
__________________
Jim

'96 A6Q - 180+K miles

Last edited by Midniteoyl; 04-26-2009 at 11:29 PM.
  #7  
Old 04-26-2009, 11:28 PM
Jackmup's Avatar
2nd Gear
 
Join Date: Mar 2009
Location: New York
Posts: 1,227
Points: 7,872, Level: 59
Points: 7,872, Level: 59 Points: 7,872, Level: 59 Points: 7,872, Level: 59
Level up: 61%, 78 Points needed
Level up: 61% Level up: 61% Level up: 61%
Daily Activity: 26.5%
Daily Activity: 26.5% Daily Activity: 26.5% Daily Activity: 26.5%
Default

You can go to bentleypublishers.com for the repair manual that will have a wiring diagram in it. I would start chasing the wires back as far as you can looking for damage like midniteoyl said. You will only make it so far though you need to look for power from the relay down until you find the break.
__________________
02-A6 Quattro 3.0 Avant
00-A8 Quattro 4.2
  #8  
Old 04-27-2009, 12:33 PM
SloRide's Avatar
1st Gear
 
Join Date: May 2006
Posts: 140
Points: 6,373, Level: 52
Points: 6,373, Level: 52 Points: 6,373, Level: 52 Points: 6,373, Level: 52
Level up: 12%, 177 Points needed
Level up: 12% Level up: 12% Level up: 12%
Daily Activity: 0%
Daily Activity: 0% Daily Activity: 0% Daily Activity: 0%
Default

Thanks.
I will look around for a broken wire or a fuseable link. The only power at the relays is for the coil only. There is no power on either termanials that would switch the 12 volts to the fans. where ever the power TO the relays is coming from must be missing. Gotta dig some more.
***
Edit. Went tracing back wires at the engine plenum relay box today. (Audi is real good at using color coded wires) It finally led me to another fuse and relay box, located behind the kick panel on the drives side. Inside were 4 more relays and 1 big ars 60 amp fuse that was labled 'radiator fan' and it was blown. I replaced the fuse and the fans came back! Thanks to all for the input.
After messing with this for a few hours I'm going to search on 'fuse and relay locations'.
__________________
Earth First! We'll ride the other planets later.

Last edited by SloRide; 04-28-2009 at 09:06 AM.
  #9  
Old 06-22-2009, 08:11 PM
1st Gear
 
Join Date: Jun 2009
Posts: 9
Default

I've been having the same problem.. My Aux radiator fan isn't coming on. I checked the fan, it works with 12V directly to it. upon getting under the dash to check the relay I found a 30amp fuse that was blown. I changed it and the fan started working perfectly for about 5 minutes then it blew again.

Any ideas what could be causing the fuse to blow?

Thanks in advance,
Chris
  #10  
Old 06-22-2009, 08:27 PM
Midniteoyl's Avatar
4th Gear

 
Join Date: Mar 2009
Location: Indiana
Posts: 3,041
Points: 6,139, Level: 50
Points: 6,139, Level: 50 Points: 6,139, Level: 50 Points: 6,139, Level: 50
Level up: 95%, 11 Points needed
Level up: 95% Level up: 95% Level up: 95%
Daily Activity: 3.6%
Daily Activity: 3.6% Daily Activity: 3.6% Daily Activity: 3.6%
Default

-That fan is pulling too much current

-Theres a short

get the .zip and trace it.
__________________
Jim

'96 A6Q - 180+K miles
Old 06-22-2009, 08:27 PM
 
 
 
Reply


Tags
a3, air, audi, b5, control, engine, fan, fans, flap, flow, forums, fuse, location, motor, open, potentiometer, radiator, relay, sporadic, tt, working


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Advertising

Featured Sponsors
Vendor Directory
New Sponsors

All times are GMT -4. The time now is 01:42 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Internet Brands, Inc.
Emails Backup