1985 300SD 617 Aux Fan & A/C Thoughts + Help Needed

[Hit Man X]

FINALLY finished the rebuild of the AC in my 300SD. I easily spent a week alone flushing the system as it was that disgusting and a few evenings alone working on aligning the bastard W126 expansion valve a few times to flush the evap core... whoever allowed that to be stuffed in there needs their ass removed. Had to track down proper fasteners for the compressor (the washer shims), rebuild the harness under the hood, and the like thanks to the PO.

Per the usual, I did an over night vac, held vac, then ... no compressor turn on. I did find this thread KLIMA Basics missing from this forum which is helpful, I DO have power from the PBU to the Klima pins (which I suppose means the PBU is good) but nothing from the Klima to the dryer or comp. I did jump the compressor and the system is now full of Dichlorodifluoromethane but obviously, I would like to fix it properly.

I appear to have a fried connector (tracer? I do not know the proper term) on the PC board so I'm going to get a new Klima for sure. What the hell do the two relays in the Klima do? Do both have to trip for the clutch to lock?



On a related note, my aux fan isn't working. Direct 12V makes it run high speed so at least it works that way. It will not come on at the fan connectors at the dryer.

Where is the relay for this and where is the resistor for this?



Thanks