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 06-15-2000, 10:59 AM
Registered User
 
Join Date: Nov 1999
Location: Dallas, TX
Posts: 81
My car has developed a strange thing.
When it rains and the streets start to have puddles and you drive over puddles the A/C Compressor cuts out. Subsequent to that the windows fog up and I have to stop. No matter which button I push or even push 0 the compressor will not come back on. The flaps and the temp regulation works just fine however. Indicating to me that the push button unit is problably ok. If I stop the engine and resart the car the A/C compressor comes on immediately and stays on until I drive over another puddle. It seems like I am shorting out a connection, but how would that fix itself when I restart the car. I don't know. Could it be the KLIMA relay?
All the other AC functions work just fine in the dry, only when you drive over a puddle is whenthe problem occurs. I had plent of opportunity to verfy this, yesterday as we had some heavy rains.
Any leads?? Thank you guys in advance.
By the way its '86 300E

[This message has been edited by Mino Erhan (edited 06-15-2000).]

Reply With Quote
  #2  
Old 06-15-2000, 01:22 PM
Terence
Guest
 
Posts: n/a
HiMino,
Seems like your 300E belt slips when you drive through the puddle of water. When the belt tensioner gets loose or slippery, the air-con compressor would cut off, preventing engine load. Anyway, there is only one long belt(air-coin, alternator, fan etc...). It occurs quite often to Merc 300E's. The air-con is sensitive to engine timing as well. One other problem that leads to A/C compressor cutting off is vaccum leak.
Solution : check your belt tensioner, maybe time to change!!!
Alternatively, if you do not want any of the above causing A/C compressor from cutting off, you gotta get somebody to modify your A/C relay so that it does not have any feedback sensing.
Reply With Quote
  #3  
Old 06-15-2000, 07:24 PM
Registered User
 
Join Date: Mar 1999
Location: Suwanee, GA, USA
Posts: 4,712
Where is the belly pan? It will prevent this. One of the factory test procedures is pouring water on the belt to see if the cut out is working. Install the belly pan.

------------------
Benzmac:
Donnie Drummonds
1992 500E (very soon I hope
1981 280GE SWB
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM
Reply With Quote
  #4  
Old 06-15-2000, 07:31 PM
Registered User
 
Join Date: Nov 1999
Location: Dallas, TX
Posts: 81
Well, the belly pan is the big plastic cover that attaches to the body with 6 screws, right?
It's there.
I have about 30K on the belt. Its time for a new one anyway, the tension is ok howerver. Thanks for the water pouring tip. I'll try it now.
What else could it be?
Reply With Quote
  #5  
Old 06-16-2000, 12:14 PM
rhinobenz
Guest
 
Posts: n/a
I was experiencing a similar situation with my 89 300E. However mine didnt trip when it was wet. It would just cut out after about 10-15 minutes of use. Then, if I restarted the car the process would repeat itself. At first we tried replacing the belt as it was badly worn and likely slipping. However when that didnt eliviate the problem, my mechanic found that my A/C relay was at fault. About $250 later and Presto! Problem solve. That was last fall. Now its broken again. imagine that.
Reply With Quote
  #6  
Old 06-17-2000, 10:50 AM
LarryBible
Guest
 
Posts: n/a
Mino,

This car has a circuit that cuts out the AC if it senses a slipping built. I would expect that there is a problem with the belt tensioner. Check it out, repair or adjust and replace the belt. This is most likely your problem.

Good luck,

------------------
Larry Bible
'84 Euro 240D, 523K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in
Mercedes automobiles
Reply With Quote
  #7  
Old 06-18-2000, 01:20 AM
jrd jrd is offline
Registered User
 
Join Date: Jan 2000
Posts: 52
Hi! I have an 87 300D with a similar
(but somewhat different) problem.

I just got my car back from a shop in
Santa Cruz getting my A/C leaktested,
fittings tightened, and the system recharged.
Blew nice cold air! ... Until I hit highway
17 on my way to Oakland. I started climbing
the hill and the air suddenly smelled
damp, then became outside temperature (80-ish).

I got pretty pissed, so I pulled over, cooled
the engine a minute, shut off, restarted.
The A/C worked again.

Then the A/C worked fine on a flat surface,
but when I started climbing the hill again,
it cut out. I was glad I had a 12 pack of
Coke next to me on the front seat, as it
was easily 100 degrees in San Jose.

The serpentine belt and tensioner are 8k
miles old.

If I just leave the car sitting stationary,
the compressor works fine.

Do I need to get the clutch adjusted, or
is the relay suspect? (Are either expensive?)

Warmly,
Justin Dobbs
Reply With Quote
  #8  
Old 06-18-2000, 01:52 AM
rhinobenz
Guest
 
Posts: n/a
Justin, it sounds like you are going through exactly what I did. Hope for a problem with the belt as it is inexpensive to replace (it cost me around 70 bucks to get a new one installed). However if your belt is in OK condition I would say that your A/C relay may be shorting out as was mine. It cost me about $230 to relace (I think the relay itself represented about half of the overall cost and labor the other half)
Good luck
Ryan
Reply With Quote
  #9  
Old 06-18-2000, 09:17 PM
jrd jrd is offline
Registered User
 
Join Date: Jan 2000
Posts: 52
Rhino,

I will keep the relay in mind as a possibility.

I had to replace the serpentine belt 8k miles ago due to oil from the vacuum pump. I don't imagine oil would be causing the belt to slip, since I hear nothing, the belt is tight, and everything appears to be clean
(pulleys shiny).

I also plan to replace all fuses in the fuse box with a new set I have in the glovebox and keep the old ones as spares.

Also, this only seems to be happening when it's really hot--the time I need the AC! Today I drove the car hard up and down hills in 70 degree weather and the AC cooled great--everything worked like a champ. Wait till it gets warm and the AC stops working.

The compressor clutch gap, when I look down from the top, appears to be 1-2 mm.

Does the aux water pump cause this, or does this occur only when the heat is on?

Thanks!
Justin Dobbs
Reply With Quote
  #10  
Old 06-18-2000, 11:11 PM
rbdrost
Guest
 
Posts: n/a
Justin may have hit on the solution - the auxillary water pump. Within the past year we have had a 300D with an A/C problem - compressor would cut out - and it turned out to be the aux water pump. Found the problem quite by trial and error after trying all the "scientific" things and having the car on test equipment. We found the problem by simply unplugging the pump and finding the A/C worked fine when we did this.


------------------
Bob1
Reply With Quote
  #11  
Old 06-18-2000, 11:33 PM
Super Moderator
 
Join Date: Apr 2000
Location: Falls Church, VA
Posts: 5,318
Here is an except on how to bypass the root of all evil - the Klima relay - that appeared a couple of months ago. I am going to try this on my 300E, and it should cure your problem.

Excerpt follows:

GERMAN AUTOMOTIVE
Member
Posts: 15
FromALMDALE CA. U.S.A.
Registered: Mar 2000
posted 03-17-2000 03:44 PM
------------------------------------------------------------------------------
--
THE COMPRESSOR RELAY CAN BE BYPASSED AS FOLLOWS,USING RELAY # 001 542 02 19
MAKE YOUR OWN JUMPER WIRES. TERMINAL #1 ON KLIMA TO #85 ON ICE CUBE,#10 KLIMA
TO #86 ICECUBE ,TERM. #5 KLIMA TO #30 ICECUBE,AND #7 KLIMA TO #87 ICECUBE.
CLUTCH WILL ENGAGE AND DISENGAGE AT PUSHBUTTON ASSY'S COMMAND.M.F.
------------------
M.F.

IP: Logged

BRAD
Member
Posts: 11
From:SUMNER, TX 75486
Registered: Mar 2000
posted 03-17-2000 04:48 PM
------------------------------------------------------------------------------
--
THANKS TO GERMAN AUTOMOTIVE M.F. WILL THE COMPRESSOR STILL BE CONTROLLED BY
THERMOSTAT CONTROL WHEEL? ALSO WHAT ARE YOU REFERRING TO AS ICECUBE?
------------------
BRAD FRANCIS
1986 190D 160,000 mi.
SUMNER, TX

IP: Logged

Benzmac
Moderator
Posts: 3251
From uluth, GA, USA
Registered: Mar 99
posted 03-17-2000 09:11 PM
------------------------------------------------------------------------------
--
I have had to do this with 134 conversions because of the higher pressures.
It does work. The ice cube is a generic term for the Bosch 5 pin relay. You
can get one at any stereo shop... It will be controlled by the pushbutton and
will cycle on and off yes./.
------------------
Benzmac:
1981 280GE SWB
1987 16V
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM

------------------
Chuck Taylor
Falls Church VA
'86 300E 5 speed
'95 C220 (wife's car)
'98 Porsche Boxster
Past: '79 280E, '82 300D (18 yrs), '77 240D,
4 250C's
Reply With Quote
  #12  
Old 06-20-2000, 12:34 AM
jrd jrd is offline
Registered User
 
Join Date: Jan 2000
Posts: 52
All,

Thank you for the suggestions regarding the air conditioning compressor cutting out on my w124.

I have disconnected the auxilliary water pump connector under the windshield reservoir. It was so corroded that I could barely get it apart. I used my A/C for at least 30 miles today and it cooled great, and the climate control held the temperature quite nicely.

Whether it works this well going to San Jose next Sunday, and through SJ to Oakland the following week, remains a mystery. Since it worked great in cooler weather but seemed to cut out in warmer weather, this makes me suspicious that something like coolant temperature, coolant volume, or something else was triggering the A/C compressor to cut out. I am a little suspicious about the aux coolant pump.

Nevertheless, I plan to bring another 12 pack of Coca Cola--JUST IN CASE .

Thank you for the helpful suggestions. If the coolant pump disconnection fails to rectify the problem, I will investigate the Klima relay. I'm a little weary of bypassing it, as I do not want to lose power steering or something else if my compressor locks up.

I will keep you posted.

Thanks!
Justin Dobbs
Reply With Quote
  #13  
Old 06-20-2000, 08:30 AM
Registered User
 
Join Date: Nov 1999
Location: Dallas, TX
Posts: 81
I tried the water pouring trick and I was able to make slip, to emulate the cutout problem. I works with quite a bit of water. I will take the advise and replace the belt, in hopes that this will cure the problem.

Thanks for all the input.

------------------
Regards

Mino Erhan Dallas, TX
'86 300E
'67 Peugeot 404 Conv.
'85 Peugeot 505 STI
'99 Suzuki GSF 600 Bandit

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
'84 300SD W126 - A/C clicks off dead once it reaches dialed in temp bodyart27 Diesel Discussion 7 08-12-2005 03:19 PM
Winters over and A/C season begins pdxman Diesel Discussion 7 03-13-2004 01:38 PM
91 300SEL - Idle drops when A/C is on Mike Murrell Tech Help 2 09-05-2003 08:27 AM
'84 300SD W126 - A/C Question - the saga continues bodyart27 Diesel Discussion 13 06-23-2003 05:32 PM
Bad odor from A/C and Refrigerant leakage Holson Adi Tech Help 5 01-17-2003 02:00 PM



All times are GMT -4. The time now is 10:25 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page