[gprocket]

What a week. My plant uses machines that operate using PLC (programable logic control) computers. One of them went out and as it turns out is NLA and unrepairable. So all week we had to rewire and reprogram the machine systems. Finally got it back online after 10 days. The hard part was that no one including myself knew how to do this. Was not unlike trying to troubleshoot a misbehaving 164. Speaking of which...

Swapped in a good heater core (thanks for the link to the write up) and we solved that issue. But in the best tradition of the Alfaworld fixing one problem revealed two more.

First we noticed that the wiring going from the speed control unit to the blower motor was getting really hot. Some previous fix had replaced the 4m wire with a 1m wire and effectively introduced a nice long resistor in the circuit. Then the AC pump clutch would not come on. The outside air temp was registering -40F (about 130 degrees off) so I figured the clutch wasn't being asked to do engage. After a lot of horsing around we traced it to a faulty ECU. A good unit was swapped in which solved the temperature problem but the clutch still is a no go.

I am going to check to see if we are getting 12VDC at the clutch. I searched but as yet have not found the Q22 AC clutch relay. Any ideas?