Blower motor woes.... Help! Please! 93 400E Mercedes

I just bought this Mercedes and everything is great about it except...The blower motor does not turn on. I pulled it out and bench tested it, works great.

The strip fuse is intact, All fuses (4, 6 and 7 checked twice) tested with multimeter and good.

All the vent flaps and such seem to move correctly.

When driving air comes out vents, its the breeze I guess.

I bought a new regulator before getting some brains and found out I have no 12 volts to the firewall block behind the brake booster. The yellow wire shows some voltage. Black shows none (which I hope is good because its a ground right?)

Well now that I have spent hours and days, and some hand scrapes on this, is it the climate control unit? or the ignition? or a melted wire?

Any help would be appreciated, I love this car but the blower motor will keep it from getting licensed for sure.

Reply to
macdrone
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Whar in tarnation do ya live thet ya gots ta worry bout a blower motor fer licensin? Down hear we need 4 wheels wif tires an a steerin wheel an a motor an sum lites. Oh yeah - we needs us a muffler too, an then ya gots ta put a horn on it cause its too quiet wif them ole muffler. An ifn them turnin lites iz out, ya better have a way ta put yer arm out ta let em know which way ya iz gonna turn before ya turns. My ole

92 400E had alla them thangs but ah caint rememba no blower lessen they wuz one in tha heater an cooler thangs.

mcbrue welcominglytaSC under the bridge in the trailer down by the river

06 ** ***
Reply to
mcbrue

Whar in tarnation do ya live thet ya gots ta worry bout a blower motor fer licensin? Down hear we need 4 wheels wif tires an a steerin wheel an a motor an sum lites. Oh yeah - we needs us a muffler too, an then ya gots ta put a horn on it cause its too quiet wif them ole muffler. An ifn them turnin lites iz out, ya better have a way ta put yer arm out ta let em know which way ya iz gonna turn before ya turns. My ole

92 400E had alla them thangs but ah caint rememba no blower lessen they wuz one in tha heater an cooler thangs.

mcbrue welcominglytaSC under the bridge in the trailer down by the river

06 ** ***
Reply to
mcbrue

In Illinois it is a requirement to have a front window defroster that works. Any real help would be appreciated.

Reply to
macdrone

I'm sure you thought of this, but just in case: If the motor works, but there is no air when you activate the control, the problem must be in your control circuit. The control always activates relays.... check the appropriate relay

cheers, guenter

Reply to
Guenter Scholz

I have found no relay, I was told and see that it is fused all by itself. In the diagram I see no relay. I just cant find where that one wire start from and goes to that riser under the hood behind the brake booster. I have heard rumor it comes straight from the ignition, It is a weird bird of a problem. Thanks for the reply.

Reply to
macdrone

What is the voltage like on the other side of the existing blower switch when it is turned on? (assuming you have a manual control and not the automatic cc). If it is the automatic cc is the thermostat in the cabin good?

Why not run a temporary wire through a switch from the fuse box to the firewall until you find where that other wire goes?

Reply to
me

That is a decent idea, but will that hurt the climate control unit? or something like that?

Reply to
macdrone

I just put in a brand new voltage regulator, but there is no 12v constant getting to it. Sorry to reply in two posts didnt see the last part of you reply. Thanks again all for the ideas so far.

Reply to
macdrone

Bently MB owner's Bible says fuse 12 fails, and to bypass with another.

These may be useful:

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Cheers, ws

Reply to
ws

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Status Guys (almost figured out me thinks) Put 12v to that red lead and on low no prob, on defrost high speed no prob, high speed a/c POP! Didnt try heat high speed but the first fuse POP! was enough to scare me so I didnt burn up that 217 dollar regulator. So I hear that AUX WATER PUMP or the A/C comprssor with low freon also maybe the culprit for blowing the motor fuse? Or maybe bad bearings in the motor. giving too much load? When I hooked up the motor directly to the battery with the fuse it didnt blow, just when I piggy backed it to any other fuse (not even in use). Thanks for the LINKS! that did help. This group is great.

Reply to
macdrone

I still need some help figuring out why the fuse keeps poping at high speed? Any ideas? As far as I have seen the motor is the only draw on that fuse, so is it the motor? Thanks.

Reply to
macdrone

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