Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Tech Help

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 10-12-2004, 08:49 PM
Registered User
 
Join Date: Feb 2002
Location: Clearwater, FL
Posts: 46
Cooling Problem - Aux Fan???

I have an '88 300SE with 250K+... still running great.

Today I noticed that while stopped in traffic my temp gauge kept climbing. As soon as traffic began to move, the temp went back to normal. I later pulled over and allowed the temp to climb while the engine idled with the AC on. I noted that the aux fan never came on. I later verified that the fan was OK by applying direct power.

My question is, could it be a temp sensor?? Do these fail??
Where is the temp sensor located for the aux fan??
Is there anything else that might the problem?
Maybe a resistor?
Any suggestions are greatly appreciated.

Reply With Quote
  #2  
Old 10-12-2004, 08:57 PM
Gilly's Avatar
Registered User
 
Join Date: Mar 2001
Location: Evansville WI
Posts: 9,616
Could be the AC high pressure switch, it depends though on if the pressure in the AC system was high enough to turn it on, this would be low-speed fan, it could also be the low speed relay.
The engine temp has to be quite high (usually up over 100c) before the high speed fan will come on, so unless you were really that hot, I wouldn't worry about the high speed fan but maybe the low speed fan.

Gilly
Reply With Quote
  #3  
Old 10-12-2004, 09:16 PM
Registered User
 
Join Date: Feb 2002
Location: Clearwater, FL
Posts: 46
Thanks Gilly.

Actually, the temp did rise over 100c,,, it was just south of red linning without the aux fan turning on. In the past, I would usually hear the hi speed fan cycle on and immediately see the temp drop. My aux fan is the single, larger type. Any other thoughts??
Reply With Quote
  #4  
Old 10-12-2004, 09:26 PM
Gilly's Avatar
Registered User
 
Join Date: Mar 2001
Location: Evansville WI
Posts: 9,616
When I mention "high speed" and "low speed" fan, it is the SPEED of the fan, not "one fan is high speed" and "the other fan is low speed", I realize there is only 1 physical fan.
Try shorting together the 2 wires on the high pressure switch and see if the fan come on low speed. If you juped power and ground to the fan and it runs, you need to find out why it isn't coming on. You can also check fuses in the small auxillary box where the fuse are for the fan.

Gilly
Reply With Quote
  #5  
Old 10-12-2004, 10:52 PM
Registered User
 
Join Date: Feb 2002
Location: Clearwater, FL
Posts: 46
Thanks again.
Sounds like the small auxillary fuse box is a good place to start as I didn't realize there was one for the fan...
Reply With Quote
  #6  
Old 03-25-2005, 02:22 PM
Registered User
 
Join Date: Dec 2004
Posts: 46
auxillary fan not working

You can also check fuses in the small auxillary box where the fuse are for the fan.

Gilly[/QUOTE]

Hi need to know where this fuse is located...had my mechanic hotwire the fan to work with the ac ...Thanks for all inputs

__________________
1993 Lexus SC300
1987 Mercedes 300E ..totaled out..
1991 Saab 900Convertible ..gave away..
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

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 On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 01:18 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2021, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page