My perfict 1987 560SL with only 80,000 miles suddenly stopped cooling last Saterday. The car is driven only on sunny days with the top down once or so a week. Kept in garage always. The AC has until Saterday worked perfect including that tempramental climate control that has malfunctioned on my other MB cars. No apparant freon leaks, just blows unconditioned air! As the car has been cooling us on 90 Degree days with the top down until this drive am I correct in suspecting a relay? I see (2) types of relays listed : one called AC temperature relay and one called simply AC relay for 560SL. Could somone give me a direction to problem.

thanks much......

I suggest you don't start messing with relays until you've first checked the basics.

Open the hood and look to ensure that the compressor clutch is kicking in when a/c is turned on max cool and max fan. If it does, then look at the sight glass to see if there are bubbles. If there are no bubbles AND the clutch is turning the compressor, then it is low on refrigerant. Find and repair the leak and recharge with R12.

If it does not, hook up manifold gauges, or have them hooked up by a shop and check the charge. If it is low, find and repair the leak and recharge with R12.

If you determine that the system has adequate refrigerant first, THEN you can start troubleshooting the electric circuits, preferably not by just shotgun replacing relays. Start at the pressure sensor and electrically work back toward the relays.

Good luck,