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Old 08-04-2007, 08:59 PM
juicy5 juicy5 is offline
Registered User
Location: Phoenix, AZ
Join Date: Aug 2007
Posts: 11
Mein Auto: 2001 325i
Final Stage Resistor Install 2001 325i

I use this site all the time and benefit from all the great advise. So here's my contribution....I couldn't find detailed instructions on how to change out the Final Resistor (FSR) so it took me awhile to figure it out on my own. This is definantly a DIY job. All you need is phillips screwdriver, flathead screwdriver, hexhead screwdriver, and a flashlight. The part cost me $111.62 at the dealer. It has been updated from the original design. My symptoms where; started with the blower blowing at variable speeds on it own. Made some wierd noises. Then one day it just stopped working. The lights on controls still worked fine, and I could hear the compressor kicking on, just no air blowing. Before replacing the part, first check the fuses (fuse #50).

Here we go....
1. The FSR is located on the passenger side beneath the dash (if you are sitting in the passenger seat it will be up above your left foot).
2. Remove the glove box. First open the glove box and remove the three screws along the top. There are two more screws tucked back in (just look with your flashlight, you can't miss them). Now close the glove box and there are some screws underneath that will need to be removed. I believe there are six screws (two near the front and four that hold the brackets on). Once all the screws are removed, rattle the glovebox a bit and pull towards you. It should come out very easily. There will be two harnesses connected to the glove box that you need to disconnect. That should be it. --Five minutes--
3. Behind where the glove box came out, you will see a black flat platic piece that needs to be removed. Start by pulling on the right side of it (straight towards you, not down), and then the left side has a clip. Once the right side is pulled out, you can push on the left side and it will unclip. Disconnect the light harness. That should be it. --One minute--
4. Now, for the fun part. You will see the foot air supply vent up and to the left (you need to lay on your back and look up with flashlight. A little above and behind the foot vent you will see the FSR. There are two harnesses you need to disconnect (one connected to the FSR, which can be disconnected by squeezing the two side clips and pulling and the other is small one that is attached to the same wiring). --Three minutes--
5. Take a beer break.... --Five minutes--
6. In order to get to the FSR you will have to remove a couple more pieces. The first is a black plastic round looking thing that is obstructing access to the FSR. Unclip the bottom of it first and then stick a small flathead screwdriver on the top of it to push down the plastic tab holding the other end in. Now there is another plastic piece that needs to be removed. There are two hexhead screws holding this on. The first is easy to see and get to (it's on the bottom right of this piece). The second took me some time find. You really have to put your neck at an uncomfortable angle. It is on top left of this piece and is very difficult to see (shine your light back there and you will see it shining). You need about a six-inch extension to get back in there to remove it (I would suggest a magnetic head so you do not drop and lose the screw). Now, the black piece in front of the FSR should slide out (be careful, there is a platic link that connects to this piece and operates the flap DO NOT BREAK IT). It does not need to be disconnected or removed, just push it to the side. --15 minutes--
7. Now it's time to pull out the faulty FSR. The only thing holding this in at this point is the one clip. There's not much room to push the clip back far enough, so use a flathead screwdriver to get inbetween the plastic clip and the FSR and use a little muscle. The FSR should slide right out (might have to wiggle it back and forth a little bit). --Five minutes--
8. You're ready to install the new FSR. Plug it in first and turn on the car to confirm the problem has been resolved.
9. Now follow the steps in reverse and put it back together.

This job took me about two hours, but I took apart both the driver and passenger side to find this thing. If you follow the steps above, I don't think it should take you any longer that an hour to an hour and half. Just be patient and don't break anything.

I hope this helps. Sorry I don't have any photographs. Good luck!