Results just in from both vehicles:

red to black= 12v
red to yellow=2-2.3v
yellow to black= 10v

To get access to the blue wire do I pull the Wiper assembly? Thanks.

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51 willys M38
62 willys M38A1
79 chevy
92 300D
95 300D
96 vision recumbent
2004 Wrangler

Ok

You have to go down to blower ..when you get there , test for 12v at red wire on blower w/key ON...if YES,.. then ground the blu wire at motor with a jumper..if that gets you full fan, you have a bad regulator or no trigger voltage to reg [ yellow wire ]

http://www.peachparts.com/Wikka/W124BlowerMotor

__________________
A Dalton

Dalton, I appreciate your simple test procedures. I am having what I believe to be regulator issues and will use your test to confirm. My question, however is, what leads the regulator to go bad?

In my case I have a 124.133 (87 300D Turbo) and at about the 21 year mark the fan stared to make grinding sounds (over months) and died...figuring it was probably bad, I replaced it to find the fan didn't run "as it should". Would a failed blower motor cause the blower regulator to fail?

Additionally, I have one observation on my installation of my blower motor...I noticed that on hook-up and checking its performance before reassembly of the unit that the motor (with ignition on) runs constantly. Do you have any comments on this with regards to correct functioning of the control unit and regulator?

Mike

__________________
MIKE
1987 300D Turbo, 225K
124.133/603.960

(I had to post this to subscribe to this post)

__________________
MIKE
1987 300D Turbo, 225K
124.133/603.960

Regulator failure is usually caused by high blower circuit Amp draw due to bad/worn motor bearings or brushes.
Also caused by lack of maint. of cabin air filters , but that does not apply to your chassis [ only later systems w/filtration.]

__________________
A Dalton

Grounded the Blue wire today. Motor runs fast and strong, looks like I'm in for a regulator. Many thanks for all the help.

I have parents that live in Florida/N.H. We're headed out that way next month.

__________________
51 willys M38
62 willys M38A1
79 chevy
92 300D
95 300D
96 vision recumbent
2004 Wrangler

<>

Both states ??

W124 Blower Motor Removal Photos
W124 Blower Motor Removal Photos - PeachParts Mercedes ShopForum

MONO BLADE VERTICAL parked windshield wiper
Build a Free Website with Web Hosting | Tripod

Hesitating Wiper Repair
202Tech - Hesitating Wiper Fix

Blower Motor and Blower Regulator Replacement 1993 300E
http://www.davebarnhart.com/mb300E/Blower/Blower3.htm


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I know this is an older thread but lets see if you guys can help me figure this out.
When i measure the voltage at the 3 pins with ignition on CC at defrost and fan high, I get 0 volts on all pins.
With ignition off I get
10v on red/yellow
12.1v on black/red
Fuse link at shock tower does the same. It has 12V going trough it with ignition off 0V with ignition on.
What now?

I've replaced the CC unit and tried again with CC temp wheel set to max heat, defrost, fan high.
This time
12V bl/rd
2.2V rd/yl
Than I thought thats it, I put the plug back in and the blower motor turned on.
Until i switched the ignition off and on again now it's dead.