So my blower motor has not worked since I bought this car (92 300 te 4matic), I had varified that the 2 blue fuses for the blower are good, and that there is power going into the interior heater control switch assembly. But today I got into the blower, and found no power reaching the motor, (I tested both the red and blue wires at the motor, and the 3 pin loom (red,black,yello)that runs from the motor area over to it's mount just behind the master cylinder.) No power or ground at any of these places. I ran direct power to the motor also, using first the motor body as a ground and then the blue wire (though I assyume it is actually a second speed power wire), but it does not spin.
I need this car as a daily and could really use some advice on the next thing to check.
Thanks, Michael

Use the search, great information already here. You test for voltage where the connector comes out of the firewall, not the piece in your hand. One is always hot (with ignition on), one is ground, and the yellow one is control voltage from the ccu unit.

When at the blower, grounding the blue wire should run the motor (ignition on). Follow what you find in the search to the letter (Arthur's posts) and you can't go wrong.

I just replaced my regulator which crapped out 1 year after motor replacement. If I was to replace another motor, I'd do the regulator at the same time if I thought it was the original one.

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Hanno
'79 6.9 Sold (after 27 years)
'83 280SL, 5 spd.
'94 E320 Sdn. 5 spd conversion
'02 E320 Sdn.(on loan to mom!)
'87 300E (5 spd. conversion) Sold
'05 E500 Wagon

On the driver's side strut tower near the hood opening there is a small black compartment, inside of which there is a blower "strip fuse".

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Gone to the dark side

- Jeff

Thanks, that strip is ok too. I am guessing that it is the regulator that is under the blower case. I still can't figure why there is no power at any of the blower wires, and the multiple fuses are ok. Are these known for switch problems?

Yes, the regulator is under the case.

Do you have +12v and ground to the motor (check with a test light across the pins on the plug; top of the brake booster)?

__________________

Gone to the dark side

- Jeff

No power or ground at the motor. This afternoon I will proceed with diagnosis.

This is strrange, but the 30 amp fuse strip was the culprit. It looked fine and I did test it for power as one of the first things I checked, but today when I rechecked it, it had power at one end but not the other.
I didn't have an exact fuse in my box but did have this 30amp fuseable link, so I made it work. I restested for power and buttoned the blower/wiper assembly back up and it all works!

Thanks for help to all.
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