Hi,
Also having problems with '87 W201 A/C. Fortunately I have a second vehicle that I can use in the heat. I am looking at a Tempmatic control P/N 201-830-0785, a rebuilt by CCI Uptime, I have zero compressor engagement, auxilary pump was previously disconected. I will be doing more trouble shooting over the next two weeks. For more info on system, download from this site info on control P/N.
http://www.programainc.com/?go=technical_support&v=3 Keep us posted, Thanx.