You can jumper the low pressure cut-out switch and test the compressor
clutch to be certain your problem is low freon. Since the car is a '92, low
freon is the likely problem. Hopefully you can just add a pound every summer
and that will get you by.
CAVEAT!!! I am only familiar with my '86 420SEL so don't bank on what I tell
Facing the front of the car, hood up, look to the right front side of the
engine compartment, a little behind the radiator and to the right of the
radiator. You should see the receiver/dryer "bottle" with a small circular
piece of glass in the top (sight glass). Somewhere, very close if not
attached to the bottle, will be a switch with electrical leads connected via
a plug. Unplug the plug creating its two halves. Take a piece of 12 gauge
single strand copper wire, like household romex, and make a "U" shaped
jumper. Now, holding the plug half that's NOT FROM THE SWITCH, insert each
side of the U into the two female recepticals of the plug. You should now be
simulating a closed pressure switch signaling adequate freon pressure.
Therefore, the clutch should engage. You do this at your own risk as I am
not a mechanic but only a mechanical engineer.
Before attacking the A/C clutch you ought to ensure it's getting power.
There are usually some safety block outs to protect the compressor - low
refrigerant being the one I'd first check of jump for brief test purpose
Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here.
All logos and trade names are the property of their respective owners.