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Blower motor not working properly

7K views 6 replies 4 participants last post by  acousticplayerjb 
#1 ·
I did some searches for "blower motor" on the boards yesterday, and found a helpful link 202Tech

and printet it out and used it whilst doing the job which was taking the blower out and lube up all bearings and dissasemble all of the plastic bits

BUT; the blower motor still does not "rev" any more from the point 3 and up to 5. Are the brushes about to die, maybe? What else could it possibly be?

Please, any tips are great :rolleyes:
 
#2 ·
Do you mean that when you turn the control knob past 3, there's no change in fan speed?

Just wondering, are you currently living in Oslo? I was there in the summer a bunch of years ago and it was a bit chilly then! So I can't imagine how much you need the heat during the winter!

Try a couple of things...
1. Test the motor with 12 volts directly and see what happens.
2. Test the voltages coming from the blower motor regulator, on each fan speed. Hopefully you have a multimeter. I "borrowed" the image that I posted below. That's your blower motor regulator (resistor). You can hook your multimeter up to the wires that go to the motor (the blue and red wires), since those are coming from the regulator.

If the voltages increase at each fan speed, then the resistor is probably fine and then it's the motor.
If the voltages do not increase, then either your resistor is damaged, or there's a problem with the control unit, such as unclean contacts behind the control knob.

Best,
 

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#4 ·
Yeah bro, had this problem myself. It was a faulty regulator. Once I replaced that, we found it had damaged the blower motor as well so we replaced that.

All up, I got all the work done for A$825 (Australian dollars). For interest's sake, MB wanted A$2600.
 
#5 ·
Thanks guys!!! :)

Yes, when I turn the control knob past 3, there's no change in fan speed.

Yes, I live in Oslo. Right now, the winter is the hottest in 100 years (true story) so no big issues with needing heat atm. Two winters ago we had a steady -15c up to -25C(!) and that was brutal. I remember my thermostat froze in open possision, and that was no good..

I will try the volt meter. I hadn't even though of the possibility of the connections behind the knob being faulty. How do I dissasamble the knob? I remember my 98 VW Golf I just possisioned the knob in 90 degree possition and grabbed it out. This does not do the trick on this knob..

I got a quote from MB, they asked $1000 for a new fan!!!!! Robbery.. a junk yard gave me a price for $150 for a used one with the regulator thingy. I will probably consider this once I have 100% confirmed that it is the blower which is the problem. (I'm 90% sure now :) )

Thanks again for all replies!!

Here's me skiing cross country two winters ago:



 
#6 ·
Thanks guys!!! :)
I got a quote from MB, they asked $1000 for a new fan!!!!! Robbery.. a junk yard gave me a price for $150 for a used one with the regulator thingy. I will probably consider this once I have 100% confirmed that it is the blower which is the problem. (I'm 90% sure now :) )
Yeah man, here in Australia, MB wanted 1400 bucks for the blower motor and 1000 for the regulator. I got them for 425 and 310 each respectively, "aftermarket."

I quoted that, because actually it's *EXACTLY* the same part, I just got it before MB got their grubbly little hands on it.
 
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