500 SEC climat control issues

[mbfixerDIY]

I have a 1985 MB 500 SEC that I am having climate control issues with. Started with the fan not working so I replace the climate control unit with a reman unit. Everything seemed to work fine for 2 days then the fan quit working again. So I started to do a little troubleshooting - checking fuses, moving relays around in the fuse box, did wiring continuity checks for both sides of the climate control module connector pins to where they are suppose to go (mono valve, resistor pack, temp sensors on engine block, blower relay, temp relay, and temp sensors, etc and continuity was good). I've replaced the temperture control module but still no fan operations or any other type of operations. I opened the origin climate control module and didn't see anything unusual. I reconnect this unit and if I manual close one of the relays (upper left one) I can get things to work correctly. Hooked up the reman unit and another used unit I just purchased with negative results. Blower motor works if jumped, overhead recirc fan motor works, all vacuum switches worked (when manually operating the climate control module relay) as well as push-button operation on the climate control module. Any suggestions on what I'm overlooking or should be trying? Andy