I have a 1990 240 that the air conditioner has stopped working. It blows the #12 fuse. The wiring diagram shows a green wire going from the thermostat switch to some sort of soleniod. It shows another green wire coming from the same pole of the thermostat switch running to the pressure sensor. I have pinpointed the problem to the solenoid by disconnecting the pressure sensor and the fuse still blows.

For the life of me I can't find this solenoid. Does anyone out there know where this is located on a '90 model or what the purpose of this solenoid is?

 

The solenoid doesn't exist, either does relay "k" ... notice the dotted lines in the attached picture. Does the fuse blow the exact instant you turn on the switch? If so then my guess would be the green wire that goes from the thermostat switch to the pressure switch has a short.

 

Interesting. The wiring diagram I have doesn't show it dotted like yours. Might explain why I can't find the solenoid.

If I don't have a solenoid, then I am sure there is some sort of short on the wire from the thermostat to the pressure valve. With the wire disconnected from both, it measures 27 ohms to ground. I have run a new wire and now the compressor kicks in when I short across the pressure switch but doesn't cool. Must need a recharge.

Why does the diagram show this solenoid? Was it used on some models? If so, which ones?

THanks for your help