70 degree days are back. Some AC help needed - Page 2 - PeachParts Mercedes-Benz Forum

fantom71 · #16 03-02-2006, 04:45 PM

The good news is that the aux fan works.
The bad news is that when I shorted out the pressure switch, the compressor did not turn on. I tried it with the center button pushed (AC) and the top (I think it is the defroster ?). Does this mean that the compressor is bad (jeeze, I hope not)? I was able to rotate the compressor by hand (the part between the belt pully and the radiator). I did this check to see if the compressor was siezed. It probably means nothing, but it might help *shrug*.
Any ideas what should be checked next? BTW, I was unable to locate the freon fluid window as described by my Haynes manual. Do all facotry AC systems have that feature?

Thanks again for all of your help.

markg612 · #17 03-02-2006, 05:08 PM

Get a multimeter and check for power at the pressure switch with AC selected. Check your fuses, namely the strap fuse in the little tiny box adjacent to the main fuse box.

Diesel Giant · #18 03-02-2006, 08:41 PM

Repairing the Ac on the MB's are easy compared to other cars. Look here for some pointers.

http://dieselgiant.com/repairyourac.htm

Mike J · #19 03-02-2006, 08:50 PM

Diesel Giant, nice writeup. So, if I decided not to do it myself, what could I expect to lay-out moola wise at a shop?

I find in the current 80 degree stuff in Raleigh that I am only making cooler warm air.
It is just cool enough that I noticed a difference when I shut it off today and opened the windows.
I.e., it seems to be cooling some, so I'm guessing/hoping the compressor is working, but the coolant is low.
It's the 300SDL, if that makes any difference.

Diesel Giant · #20 03-02-2006, 08:52 PM

That I dont know. A/C work is usually very expensive on the labor side of things.

fantom71 · #21 03-02-2006, 09:59 PM

Quote:

Originally Posted by markg612

Get a multimeter and check for power at the pressure switch with AC selected. Check your fuses, namely the strap fuse in the little tiny box adjacent to the main fuse box.

I forgot to mention that during my first check, I replaced the fuse in the fusebox with no change. I was unable to find any small box around the fuse box. Since this is the first year of the W124, maybe it is located in some other location *shrug*. I ran the multimeter at the pressure switch, there is NO current. Things are looking bad, I think

fantom71 · #22 03-02-2006, 10:05 PM

Quote:

Originally Posted by Mike J

Diesel Giant, nice writeup. So, if I decided not to do it myself, what could I expect to lay-out moola wise at a shop?

Not sure about labor rates where you are, but here in north Alabama I was quoted $300 just for them to TRY to diagnose the system. They guessed, without seeing the car that a fix could range anywhere from $500 to $1500, depending on what is wrong. That is insane cash...

markg612 · #23 03-02-2006, 10:08 PM

You gots a power problem. The strap fuse was a refit for the older cars and a mod during production mid-87. I have two 87's onE with it originally, the other I added about 6 years back when fuse 8 melted through the fuse box.

So, time for the prints and a power hunt. there is a fuse in the back side of some of the Climate control units, BUT, considering yours is manual, I'd have to check my 201 stuff. also, skip the climate manual for the 124 as it doesn't cover the manual control unit you have.

YOU NEED PRINTS!

markg612 · #24 03-02-2006, 10:25 PM

Dale, this is a wire head job, thats my gig, I'd love to dig into this one, as I have the 124 circuits melded into my skull. (wana driver to chicago?) Absent the prints, AND a shop or a tech that has access to them, DO NOT waste your money guessing with some dope that has never seen a gray-market car. The gray market cars are typically SIMPLER than there US counterparts. They are no mysteries with them, you just need the info.

What you really need is a UK version of the maintenance manuals on CD, only because they will be in english. Our US versions don't cover the Manuel Climate stuff, BUT, the 201's cover some stuff. I'll do some checking, but I won't be able to look until tuesday/wednesday at the earliest.

MB of the 80's is Prussian engineering through and through. They invent stuff once and use it over and over "because ve engineered it right once, why should ve do it tvice." The carry over from the 190 to the 124 will be your best resource. There are manual climate 190's in the NA market, AND, repair information as well.

fantom71 · #25 03-03-2006, 07:58 AM

If this is the manual AC system, I would hate to see the auto system...