Mercedes-Benz Forum banner

1 - 8 of 8 Posts

·
Registered
87 190E 2.3L
Joined
·
31 Posts
Discussion Starter #1
Hey All,

Ok, I am stumped! I have been battling my A/C for awhile now and now I need some help. Here's what's going on. Usually I can turn my A/C on like normal and sometimes it will work fine but normally it will run for about 10 minutes or less and the compressor shuts down. The only way I can get it to turn back on is shut the car off, wait a few minutes and start it back up. When it works, it blows very very cold. Here's what's been done:

-new compressor
-converted to R134a
-new climate control head
-new high pressure switch
-new condensor

Any ideas????

Thanks,

CC
 

·
Registered
'01 SLK230,'93 190E 2.3, 1971 LS5 Corvette Convertible
Joined
·
2,186 Posts
CCWHEEL - 5/14/2005 7:05 PM

Hey All,

Ok, I am stumped! I have been battling my A/C for awhile now and now I need some help. Here's what's going on. Usually I can turn my A/C on like normal and sometimes it will work fine but normally it will run for about 10 minutes or less and the compressor shuts down. The only way I can get it to turn back on is shut the car off, wait a few minutes and start it back up. When it works, it blows very very cold. Here's what's been done:

-new compressor
-converted to R134a
-new climate control head
-new high pressure switch
-new condensor

Any ideas????

Thanks,

CC
CCWHEEL,

Is your aux. fan working? If not, the high pressure will build up and the high pressure switch on the dryer/receiver will do what it is suppose to do and turn off the compressor.

This happened to me a couple of years ago. In my case it was a blown aux. fan fuse...replaced it and it has been fine ever since.

When you turn your car off, the pressures equalize and the compressor will operate again when you re-start your engine and then shut down when the high side pressure gets too high.

Good Luck,

Dave
 

·
Registered
87 190E 2.3L
Joined
·
31 Posts
Discussion Starter #3
yes my aux. fan works fine, comes on with the compessor, shuts off when the compressor kicks off. Anymore ideas?

Thnaks,

Cory

Possibly a relay?? If so, where is it?
 

·
Registered
1993 190e-2.3
Joined
·
765 Posts
My 92 ford Escort did the same thing. I found a relay under the hood that I would unplug and bang around, and then it would work for a week or so. I got a "new" relay at the junk yard a year or two ago and all is fine. Theres got to be a relay somewhere.(sorry I don't know where it is) Maybe this relay could be tied into the signal for the aux fan also. I remember my car would go through a complete cold cycle and after the AC turned off, it would not kick back in again until I banged on the relay. Hope this might help.
 

·
Registered
'01 SLK230,'93 190E 2.3, 1971 LS5 Corvette Convertible
Joined
·
2,186 Posts
CCWHEEL - 5/15/2005 1:57 AM

yes my aux. fan works fine, comes on with the compessor, shuts off when the compressor kicks off. Anymore ideas?

Thnaks,

Cory

Possibly a relay?? If so, where is it?
Cory,

If the aux. fan is working properly, then what is the high side pressure reading when the compressor kicks off and fails to come back on? We need to determine if this is a high side pressure problem or a compressor cycling problem.

Dave
 

·
Registered
87 190E 2.3L
Joined
·
31 Posts
Discussion Starter #6
The only problem with that is that the A/C only seems to act-up while driving, if you let set and idle with A/C on with a machine hooked to it, it would probably never kick off.

CC

Where's the A/C relay(s)??
 

·
Registered
1993 MB 190E 2.6
Joined
·
30 Posts
OK I went through the same thing. Spent a lot of money trying to get it fixed. I my case the belt tenisoner was faulty. Have it checked out.

Here is what was happening to me:

Same as you the compressor would kick off and it would require a complet shut down to reset the rpm sensor/switch located at the back of the compressor. When the belt slips (just a little) the rpm sensor gets out sink with the rpm sensor of the engine thus causing the system to think the compressor is trying to lock-up thus shutting it down.

I stumbled upon it by chance when the belt squeeked and at that moment the system quick working.

I hope this helps you out.

Ripley
 

·
Registered
'01 SLK230,'93 190E 2.3, 1971 LS5 Corvette Convertible
Joined
·
2,186 Posts
CCWHEEL - 5/15/2005 12:30 PM

The only problem with that is that the A/C only seems to act-up while driving, if you let set and idle with A/C on with a machine hooked to it, it would probably never kick off.

CC

Where's the A/C relay(s)??
The A/C compressor should still cycle when the engine is idling, providing the freon level is full.
If you are referring to the A/C Compressor Relay, it is behind the battery, and it should be in the left rear position behind the Fuel Pump Relay (gasoline models).

Dave
 
1 - 8 of 8 Posts
Top