My wife drives our '87 300d the most.The other day she said it was blowing COLD air even with the temp selector on full hot.
A week later she said it was doing it again.Sure enough...the a/c compressor was running with the EC button on,temp set to hot and fan on low.I unplugged both pressure switches by the the condensor.I got the compressor to disengage but another odd thing arose.The fan quits blowing when the "O"(off) button is pressed but when you take your finger off the button it will start blowing.Push in on the button...fan goes off...let go...comes on ect,ect.Should I be looking into a new control panel? How much$$$?