No A/C at all - PeachParts Mercedes-Benz Forum

#1 07-31-2004, 05:52 PM

Where do I need to start on checking things out on my 83 300sd, The ac has been working ok, most of the time it blows medium cold to really cold, but from time to time it would not blow at all and I would have to press the defrost button to get it to blow, after I did that it would blow fine. Yesterday when I got in the car and turned it on, it would not blow at all, in fact when I am going down the highway it blows heat out of the vents under the dash??? And the blower still does not blow even when I put it in defrost. Any ideas at all? Thanks, Hudson

psfred · #2 08-01-2004, 01:50 PM

Check the climate control fuse in the fuse box. In fact, check all of them, they probably need to be replaced as they corrode and crack in service.

When the fuse goes, all you get is hot air out of the defrost vents, no temp control, no AC, no blower.

Peter

SD Blue · #3 08-01-2004, 08:52 PM

I don't know how long you have had the car, but here is something I came across with an intermittent problem:

Pull the fuse completely out and look at it, esp. if car is new to you. I found a fuse where the fusible strip in the middle had separated from the end cap. Evidently the PO had "spun" the fuse so much it had worn through. It checked fine with a meter and had me "chasing my tail" for a while.

#4 08-01-2004, 11:50 PM

Boy do I feel dumb, it was a fuse, although it looks good it is not. Today I went ahead and replaced all the fuses and it works alot better, in fact it even fixed what I thought was and intermittant short in the hazards. Thanks guys.
Hudson

leathermang · #5 08-01-2004, 11:57 PM

Well, at least it was a cheap fix... .

rhino · #6 08-02-2004, 12:12 PM

might do a search too, just for fun. There's a thread out there on re-soldering some part. Just thought of it cuz one of the key indicators was having to punch defrost to get it to work again.