Door locks

[Jonoknut]

I have a 98 323is, and the power door locks werent working when i picked it up about a week ago, no alarm on the car. I checked the fuse first naturally and it was blown, i replaced it, and it worked for a week, but tonight they stopped working again, i put in 3 other fuses and as soon as they made contact they blew.... and yes im using the right type.... Any ideas? thanks,
Jon

[Jonoknut]

bump

[EEEEeeee36]

bump
For door locks? Well, blowing fuses usually indicated a short in a motor; meaning bad motor. In my experience when working on vehicles and fuses kept blowing it was a motor or maybe a regulator; very similar to power window motors. The central locking system if fairly complex compared to other systems, but it could be something as simple as the lock motor on it's way out. When you use a motor 1000x more than you use the other 3 (or 1 for a coupe) it has a tendancy to fail; for instance my driver's door window rolls up and down a lot slower than my other 3, and the motor makes a lower pitched and slower hum. That means the motor is going out and will need to be replaced soon.

The EXACT same thing that you are describing happened with my power mirrors on my E36 BTW. Would replace the fuses but every time I adjusted my mirrors the fuse would blow again, either from that or from heating up (heated mirrors). I replaced my mirrors (and of course they had new motors) and I haven't had a problem since.

Bottom line is you have a 10 y/o car and a motor that has been used excessively over the last 10 years is starting to show it's age. :thumbup:

[Jonoknut]

bump anyone else have any suggestions?

[sparkchaser]

I am inclined to agree about the bad motor. But if you want to search for another culprit, bust out the Bently, follow the circuit and see if there is a short.

The switches/motors aren't expensive and if you get them from a car being parted out, so much the better.

[EEEEeeee36]

I am inclined to agree about the bad motor. But if you want to search for another culprit, bust out the Bently, follow the circuit and see if there is a short.

The switches/motors aren't expensive and if you get them from a car being parted out, so much the better.
Yup. What a BMW technician would do is test the impedence under load of EVERY connection between your distribution block and your door-lock motor and switch to see if it is bad or not. You can either rip up your dash and start testing wiring, or you can use some logic and guess that if there are only 3 components of the circuit and you know one of them can't be the culprit (that being the fuse), then you can replace the usual suspects.

Either that or pay $106/hour for a tech to tell you the same thing. :dunno Don't worry, they'll only take 3 coffee breaks on your dime while diagnosing your car...