'80 450SL - How to run AC without Climate Control - PeachParts Mercedes-Benz Forum

supercanuck · #1 08-27-2007, 02:48 PM

Yes, another post on the climate control system.

I have a 1980 450sl that I removed the Servo on a few months back and bypassed it, just to get cold air. However, I hadn't used it yet, and the other day I went to test it out and I was not getting any air whatsoever from the AC unit.

I don't know if this has anythign to do with it, but in the process of doing so, I forgot to unplug the ac amplifier, and when I started the car back up I'm pretty sure I ruined the amp b/c it started smoking.

So my question is, what should I have to do, if anything, to get the AC just to blow cold air, without the climate control system? Does the ac amplifier or any of the other parts have anything to do with it just blowing?

Thanks!

unkl300d · #2 08-27-2007, 02:56 PM

Hi as far as I know it seems that the amp does affect the AC. But maybe not.

I had the amp replaced many years ago when my heat went out and besides getting heat back, the AC began to work again.

BUT, recently I had the amp removed because the servo got stuck ON and it was draining the battery.
The AC works (my ac is not extreme cold anyway-but I can feel the difference btw air and AC) and I hear/feel the compressor kick in when it is switched on.

check your fuses for breaks and weak ones.
check your blower fuse. if it is weak or burnt maybe the blower has too much resistance due to age....
good luck

re:'79 300D..same servo etc.

supercanuck · #3 08-27-2007, 06:12 PM

What if I'm not concerned at all with fan speed, etc etc. Basically, Id like it on or off. As simple as that. Does the amp and all that good stuff still come into play?

meltedpanda · #4 08-28-2007, 10:28 AM

I don't think so , I have mine wired direct with a little pull switch, pull out, turns compressor on , push in turns it off, Fan control still works, bypassed the servo mechanisms. I also bypassed heater pods by hooking direct cable to heater valve, pull out heat on , push in heat off

unkl300d · #5 08-28-2007, 02:43 PM

your fan (blower) should operate on different selected speeds without the amp installed.

This does not preclude the AC as being operational.

if you removed the servo completely thereby disconnecting the attached vacuum lines then your vac lines may be a source of some hang up... don't know.