I’m trying to fix my wife’s power windows in her BMW (1995 525i, I believe). I’ve got the door panels off, and I can get to the motor and gear assembly, but I can’t figure out how to get it apart so I can see what the problem is. This is the first time I’ve worked on a car in 20 years, so I’m a little out of my element.
I’m guessing that somewhere on the Web there are specs or schematics for things like this, but I can’t find them. Can one of you Doper mechanics help?
Not sure about online but the Bentley (the publisher, not the car maker) covers the five series. They used to do the factory manuals for VW and I had an excellent one for the three series bimmers.
Buy the Haynes manual. It will pay for itself eventually.
There are subscription services for auto repair information offered by most car manufacturers. I don’t know what the cost is, but I imagine it’s pretty hefty – an expense that a professional repair shop could justify, whereas an individual probably could not. I’d be shocked if the detailed technical info you’re looking for is available on the net for free. Buying a repair manual is likely the most affordable way to get it.
Yeah, finding schematics online (and free, to boot) is really hard.
I’ve looked for some and usually came up with nothing unless someone happened to scan their manuals and hosted it on a site. And that is very, very, rare.
Are you planning to take the motor apart? I’ve never worked on BMW window motor problems, but on GM and most Asian imports the motor usually comes as just that–a motor. They’re not going to sell internal motor parts, if that is what you were thinking.
*remember I’ve never worked on a BMW window problem
What are the symptoms?
Check if you are getting power to the switch (check fuses too)
Check if you are getting ground
If that is ok,
Check if you are getting power going to the motor, when you toggle the switch up and down. If you are, chances are the motor is no good…try “tapping” the motor (euphemism for banging on the motor) to try to see if you can “jar” the brushes into a temporary electrical contact.
Thanks, everyone. It looks like I’m going to have to buy the manual, eh?
LolaBaby, the problem is that the windows will go down just fine, but not up without a little push from the driver. So it’s getting power, but somehow the gears are slipping or not engaging quite right. I’ve sprayed WD-40 like holy water, so I don’t think it’s a lubrication problem.
Ok, in my experience (remember my specialty is General Motors), that usually just indicated that the motor is going bad.
Is this on just one window?
There is a possibility that there is increased resistance at the connectors, but chances are it’s not.
Did you call the dealer for prices? I don’t know about parts/brand availability where you are, but I’d bet that a BMW window motor is a dealer item. Call the regular parts stores, though. You probably would like to be 100% sure since there are no returns on electrical parts (for the majority of auto parts suppliers).
If you’re planning on keeping the car, a dealer service manual is an invaluable tool to have. They are pricey but worth it if you work on the car yourself and plan on keeping the car. Last I checked they ranged about $60 to $80, but that was some time ago.
Chilton and Haynes, well, they’re usually sold wrapped up and sometimes they don’t always have schematics or the schematic that you need.
I have an auto forum at my board (in my sig) if you’d care to ask there, but you’ll probably get the same advice there. You’re more than welcome to check it out.
BMW service manuals are electronic. They have a set of CD’s called TIS which covers all models up to the date of publication. They have tons of information about troubleshooting and procedures, including a section where you use symptoms to locate articles on particular problems. You can find them on ebay, although at least some of the ones for sale are just bootleg duplicates of the CD’s. I won an auction for $15 and this is exactly what it turned out to be.
Wow, no shit? That’s good to know. I never really thought about eBay as a source for people who need that sort of info.
Thanks. 
Are you sure the problem is with the motor? I was working on a 7-series a few years ago, also with power window problems. In my case, it turned out to be in the switches. With no manual, I turned to Google, and found a few really handy message boards. Sorry I can’t be more specific, but, as I say, that was a few years ago, and I deleted those bookmarks when I was no longer going to be working on the car.