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Blower motor will not turn off

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31K views 11 replies 3 participants last post by  mrboca  
M
#1 ·
On the way home last night the AC started to act funny: Blower was not responding to Auto. Seemed to have a mind of its own. both high and low seeds were running. When I got home the blower fan would not shut off, so at 1 in the AM I pulled the battery positive side and said see you in AM.

Checked the AC unit this am after reattaching battery and with no load on car codes seemed Normal 1,93: 2,82: 3,85: 4,85: 5,87: 6,143: 7,7: 8,91: 10, 5.5: 11, 2.5: 12, 3.6: 20, 3.2: 21, 44: 22, 0: 23, 62: 24, 13.5:

Error codes 1234 and 1235 cleared

Vents are blowing cold air Temp at center vent 55

Blower will not shut off replaced regulator resistor 2 weeks ago and all seemed fine. Have temporarily disconnected so fan won't run.

Ideas, help appreciated.
 
Discussion starter · #2 ·
I think I found the answer: previous post from MrBOCA


Also I do not understand how it turns off with the ignition OFF and door opened. There is no relationship. The regulator is between the battery and the blower motor. The only control is from the climate control. So if the climate control blower control is not adjusting the speed, the regulator is either misconnected or the driver transistor is permanently turned on (burnt). In the latter case, the blower motor will not turn off as long as the battery is connected to the car. You need to remove the power connection to the blower regulator to prevent battery drain.

If the blower regulator is burnt out, ask them to send you a replacement.

Will try this route first
 
Discussion starter · #4 ·
I just rechecked the install, there is a 3 pin connector only fits one way and a single slip on connector, so I think install is ok. part maybe be bad.
 
Discussion starter · #8 ·
mrboca said:
Inthat case, you have a bad regulator. The old style ones need to be installed on the metal blower frame with a heatsink paste, and proper torque. Yours has its own heatsink.

Just to be clear this is the porcupine style.

New Blower Motor Resistor Regulator fits Mercedes W210 E300D E320 E420 E430 E55 | eBay

This is the old style:

Blower Motor Resistor Regulator for W210 E-Class Mercedes Benz E320 E420 E430 | eBay
Click to expand...
the newer style is what is in the car and supplier has already agreed to replace, once MrBoca, thank you. Will let the thread know how this works out as soon as new part arrives, until then when I shut the car down I will unplug the blower.
 
Discussion starter · #9 ·
MJSb said:
the newer style is what is in the car and supplier has already agreed to replace, once MrBoca, thank you. Will let the thread know how this works out as soon as new part arrives, until then when I shut the car down I will unplug the blower.
Click to expand...

New regulator arrived yesterday, installed today, all seems well. Once again thank you for your help. :laugh
 
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