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Discussion Starter #1 (Edited)
I decided to post this little tutorial so others don't go through the frustration I did tonight. Recently there have been several posts about heater blower motor failures. I joined those ranks last week. My blower was operating intermittently, and when it did work, I had to have it on high to get any air movement at all. I call my local smart center, and a new motor is $287!:eek: Some have had switch failure, and some have had the resistor burn out. I traced my to the motor itself. I could wiggle the wires going into it, and change the speed of the motor. First off, after wasting 1 1/2 hours trying to figure out how to pull the heater assembly, I finally figured out it takes 2 minutes to pull the motor. Below, see the motor locaton on the heater assembly:


Next is a picture with the blower removed:


remove the connector, and simply turn the motor assembly counter-clockwise until it releases. Then pull it out.

Here is a picture of the motor out:


Remove the torx screw on the end, and you can pull the motor and fan wheel out of the plastic housing:



When I pulled the motor, the commutator was completely black. There are little white rubber covers over the brushes, pull them off, then you can move the brush springs out of the way, and clean the comm up. I started with some 400 grit wet or dry sandpaper, then moved to 600. In the next picture, you can see that the comm cleaned up nice. The motor shaft sticks out the end of the blower wheel about 1/2", I chucked that up in my cordless drill, and used that to drive it while I used my finger to hold the sandpaper against the comm. Blow it out well when your done.



Re-install in reverse order.

My fan now works perfectly, and I saved myself $300 and a 4 hour round trip to the dealer.

I'm out of warranty, that's the main reason I did this repair myself. Hope this helps some others on the forum.

By the way, these motors are built with bushings, so while I had it out, I oiled both ends as well, seemed to help.
 

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Thanks for the photos. My blower was replaced under warranty because it was making a lot of noise. It was interesting to see how easy it is to remove it. I've also fixed motors by cleaning up the commutator. It should be as good as new now, except it begs the question why it got gummed up so quickly.
 

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Discussion Starter #3
I agree, it concerns me that it blackened so quickly, I know when I pulled it out, the motor was very stiff to turn. I put a couple of drops of air tool oil on the bearings, and it seemed to free it right up. Maybe that is the culprit? Maybe the supplier(Behr) needs to improve their lubrication at assembly.
 

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Superb post. This goes to the head of my home brew technical manual.


Hey, now THERE's a good idea.

Why has no one in this community thought of compiling, editing, printing with full disclaimers and marketing the profound, collective wisdom of SOCA?
Given nothing else is available, (beside Evilution's online library), I'd pay good money for a hard copy, forum generated TM.
 

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Discussion Starter #6
Thanks for the positive feedback, I hope this helps a few people out. There is a way to get a complete tech manual for the smart see the following thread:
http://www.smartcarofamerica.com/forums/f25/mercedes-wis-workshop-information-system-22571/

One note though, part of the reason I had difficulty, is that I bought the DVD and installed it, but for some reason my 10 year access keys are no longer valid, and I have not gotten a response from the company yet as to why. I have sent them several e-mails, with no reply to any. I'll buy another set of keys(they are only $10) but if I pay for 10 years of access, I expect 10 years. I'm sure that if I had been able to access the system, I would have quickly found out the proper way to remove the blower.
 

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If that commutator was black and gummy, you had a problem. If it was just black, it was normal. Carbon from the brushes coats the commutator and the color is normally black. Also, using wet-and-dry paper is normally considered a no-no. Use sandpaper instead. The abrasive grit on wet-and-dry is silicon carbide and is electrically conductive. Any residue lodged in the gap between the commutator bars can cause problems. Most likely your problem was gummy bearings or a poor connection at the wires, since you said wiggling them seemed to help things. Regardless, congrats on taking the bull by the horns and getting it fixed on your own.
 

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Have had car for a year and 2 new heater motors installed. The last one you could kick the floor board and it would fire right up. The dealer finally admitted that they had a bad batch of motors. Mine were all replaced under warrenty. Lucky thing....dealers are 2 hours away.
 

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PLEASE can someone tell me where to find the air filter (not the cabin one)? The manual is so inadequate and has no engine compartment diagram.
 

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Mine comes on when I slap the top of the dash. Disapointing to have so many headlamp failures, a possible short and now a pending blower motor. All this so close to 24K makes me wonder if I was so SMART after all.
 

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Thanks for the tutorial. I've had my blower replaced twice and now my blower is intermittant. I'm still under the extended warranty luckily.
 

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I had a complete failure of my blower motor, and I too spent way too much time trying to figure out how to take the motor out, then I pulled the resister pac out and figured it could not hurt to try the rotation method and wala there it was. My motor commutator also was black and even after I polished it still did not word so I took the motor apart and noticed the brushes were not touching the newly polished commutator so I have my wife bringing me some hardware store brushes which I will size and shape to fit just fine. I am tired of spending the high prices for maintenance items for my car. I also had my AC go out and I found that the R134 had leaked out. Pretty sad for a car that is only 2 years old. I wonder what the EPA would feel about every smart car on the road emptying its coolant every two years!
 
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