1987-300D 124 Compressor Relay?? Help
 

Does the 1987-300D 124 have a relay for the AC Compressor. If so where is it located(position etc). I realize that the car has a fuse for the AC Compressor etc. I have tried jumpering the clutch to no avail. Any help will be appreciated. jim

Searcb "klima". On the W126 it is located on top of the firewall a little left of center.

The "Klima" relay [Klima is a brand name] is in the instrument area behind the battery. It looks at a number of inputs (engine speed, compressor drive-wheel speed, refrigerant pressure, etc.) and "decides" whether you are allowed to have the compressor's clutch engaged. It is not just a mechanical relay but a bunch of electronics plus a relay; it has been known to fail.

If you disconnect [engine off] the clutch from its 2-pin connector and connect the clutch directly to +/- 12 volts (polarity independent) you should hear a loud "clack" as the clutch engages. If you do not, the clutch is bad. If you do, the Klima relay may be bad.

Jeremy