Parts Catalog Accessories Catalog Tech Info Tech Forums
  Search our site:    
 Cart  | Project List | Order Status | Help    

Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

LinkBack Thread Tools Display Modes
Old 02-09-2003, 11:44 AM
Registered User
Join Date: Feb 2003
Posts: 4
ACC stuck in Low fan still blows heat


Yesterday my 1988 560 sel's Automatic Climate Control is not working. It seems like it is stuck in low fan but some heat is blowing. If you turn it off it still runs. If you put it in defrost, it stays the same. No changes when any button is hit. Also the recirculate switch is not working also.

Is it the push button control unit or the relay. Does it goe to this mode if the relay is blown.

Thanks in advance...
Reply With Quote
Old 02-09-2003, 12:20 PM
pesuazo's Avatar
Registered User
Join Date: Oct 2002
Location: Near Raleigh, NC
Posts: 580
Fan runs at all times

If you click the high speed button, does it go in high?
(even though the off button is pushed in)
Does your A/C compressor engages by itself?
(even though the off button is pushed in or you have it in economy mode)
Do you hear a relay clicking on and off somewhere behind the cluster and the fan is supposed to be off?
If you have any or a combination of the above mentioned symptons try taking the CCU out and resoldering the contacts to the on/off switch. I did them all for safety, now it works like a charm
1999 Porsche 996 Carrera Convertible
1994 420E - SOLD
1986 300E - SOLD, what a car
609 Certified
Reply With Quote
Old 02-09-2003, 06:16 PM
Registered User
Join Date: Feb 2003
Posts: 4

I pulled out the climate control buttons and removed the circuit board. Now, get this as I pulled the radio out I thought I would check the to see if the fan started to work so I turned on the key. Sure enough it did. So I continued to pull out the the acc control unit. Then I turned the key on again just before I unplugged it. And then it didn't work. So I unplugged it and put it on the bench and started to take the board out. I noticed a hot spot by left bottom corner on the circuit board. It was a diode. I checked it and it was still good. So I resoldered the connections and reassembled it. It still doesn't work but I did for a second. Boggles me. I did also resolder the on and off buttons but they looked good to me.

Previous post ,

Nope you can push any button and the thing stays in slow fan and heat is on. A|C does not work either. Recirc, does not work either.

I think I need a new push button control unit.... If I was working around it and it started to work. Something must be funny in there.
Reply With Quote
Old 02-09-2003, 11:49 PM
Registered User
Join Date: Feb 2003
Posts: 4
Oh yah, I forgot to mention,

I took the car for a ride and heat is blowing through every duct. The direct vents, defrost, floor, door heat. But fan is on low and again when you push the ACC buttons nothing changes in the way of directional flow of air.

This is alright for now, it is cold out, but when it warms up, it is gonna suck.

Anybody else come across a problem like this.....
Reply With Quote


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 Off
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 08:57 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2011 Pelican Parts - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page