'84 190D no heat, no blower, nada !

[Fredmburgess]

New to me '84 190D, 2.2, automatic. Bought it for something to work on (ha!)
Climate control is completely inoperative - no blower, no indication that selecting any setting or temp is causing anything in the system to operate.

-Found aux water pump seized but dissassembly, clean and lube resolved that and it operates smoothly when 12V applied to leads.

- Found a burnt contact on the large circuit board inside the C/C unit. Soldered in a jumper to bridge the gap but no improvement.

- Confirmed that fuse on back of C/C unit is good.

Is there a single fuse (not in the fuse box), relay, or sensor that would render the entire system inop? Nothing is operating - blower fan, vents, compressor.

Have searching posts for an hour - don't want to just throw in a new c/c unit if I can avoid the expense!

Thanks for any advice!

Fred

[Fredmburgess]

Just pulled the blower motor. Bearings are sloppy but it runs fine when power is applied. Found no power to the blower motor regardless c/c & fan settings. Tried re-soldering connections on the C/C board with no luck. Oh well..

My best guess would be that the seized pump toasted the CC unit.

[Fredmburgess]

Yep, that's what I suspect. Just thought I might get lucky and be able to salvage it. There was one obviously burnt path on the circuit board, which I jumped, but most likely whatever is actually on the other side of the board is toast. Hey, at least I salvaged the pump...and now I know how to get the blower motor out and was able to clean things up in there... Working in a garage, other cars to drive, life is good!

[JimmyL]

Fred,
I've been seeing CC units on ebay for a reasonable price, from folks with very good feedback. "Buy it now's" for under $60 bucks or so, with a refundable $20 buck core charge.
Good luck. Life is good!

[TX76513]

The aux pump cooking the cc is a good answer and probably, but before you through the dough on a cc unit check to make sure you have power comming from the ignition switch - another revelant issue and cheaper to fix.

[Fredmburgess]

Good idea, thanks TX. I just got online to order a CC unit but still have this nagging thought that there may be something more obvious. My first 123 had a fried board too, but that didn't kill everything like this. Think I'll get the meter back out and run through things again.

[Fredmburgess]

Tx, you were correct, did some more checking last night and found no power to the C/C circuit at the fuse box. Everything worked when I jumped it from another circuit. I did replace the C/C box since original was really fried. Expect I'll find a fault in the ignition switch when I get into it.

Merry Christmas, all. Now get off your computers !

[Brian Carlton]

Originally Posted by Fredmburgess

Tx, you were correct, did some more checking last night and found no power to the C/C circuit at the fuse box. Everything worked when I jumped it from another circuit. I did replace the C/C box since original was really fried. Expect I'll find a fault in the ignition switch when I get into it.

Merry Christmas, all. Now get off your computers !

I'm going throgh the exact same problem with the SD. Blower controller is fine. Blower resistors are fine. Blower itself is fine. Put a rebuilt climate control unit in and the blower now functions. But, the old one had signs of burning so, I'm off to pull the aux. pump today and check it out.

That damn pump might have taken out the CCU on me, as well.

A word to the wise........put a 1 amp fuse inline to the aux. pump. Make that your Christmas present. It's a five minute job on a W123. The W126 is a bit more difficult due to the location.

[waybomb]

I am curious as to how you replace the electrical part of the switch - there seems to be a major "10 pounds of chit in a 5 pound can" behind the dash of my 190!
Please post how you actually were able to get to it and replace it.
My 16v, put away for the winter, needs one, and I have one - same problem. Just no drive to go in there without some pointers!