Replacing the final stage unit/blower motor resistor (E39)

thats GBP 50 and GBP 100+

The information you provided is excellent. I am having problems with the actual AC/Heater control unit. The lights do not light up nor do any of the fan/cooling/heating options work.
Is this still a result of the bad final stage unit?

Originally Posted by gui123tar

The information you provided is excellent. I am having problems with the actual AC/Heater control unit. The lights do not light up nor do any of the fan/cooling/heating options work.
Is this still a result of the bad final stage unit?

I don't think a bad FSU will cause the whole control unit to die. Sounds like something else. But, I'd ask the mechanic when you take it in to check.

You guys rock! Thanks for all of your info. I replaced the Final Stage Resistor in about 15 minutes on my X5 and everything (AC / Heater) works like new. The tip about using needle nose pliers to squeeze the tabs and wiggle the electrical connector out worked great. I never knew that there was even a 12 volt/cigarette plug under the dash until now.

I've now replaced the FSR and two window regulators thanks to your tips/advice. Sure beats paying big bucks at the BMW stealerships.

Thanks for the great write up, I just replaced mine this afternoon. A whole lot easier than I thought it would be!!!

I cant get my hand in there to push the clip down and pull it out at the same time? Please explain

The heater control switch on my 2000 528I suddenly doing exactly what your's did, run at maximum no matter where the fan switch was set.
Stupid me, I took it to the dealer before checking Bimmerfest postings. I don't know if your marvellously detailed photos and descriptions would have helped me with my problem but as I've complained to BMW, why should they keep installing a switch that can't last 30,000 miles of benign care? So now I'm out nearly $300 for replacing it.

First of all, thanks to you elvis for writing this up and posting the pictures. As a quick tip, i just finished this procedure on my 97 540i and had some trouble figuring out how to push down on the main clip and pull out the fsu at the same time because i could only fit one hand up into the crevice. However, I noticed that the particular old unit in my car actually has a very small metal "handle" below the socket where the wire harness attaches. I found a very small "plasti-cuff" (one of those one-piece plastic things that you see the cops using for handcuffs occassionally where one end zips through an enclosure on the other end) in my toolbox and was able to hook it up to the handle with just one hand (a small allen wrench might work also??). The plasti-cuff now gave me a 4-inch handle to pull with my left hand while my right hand could sqeeze into the opening to depress the clip holding the fsu into place. It came out easily this way and I was finished shortly thereafter.

Thanks again,
David

Many Many Thanks to Elvis and all the other helpful tip posters for the FSR repair.

I think I may need to replace the FSR but sounds like, from other postings, that I need to check fuses first. I'm a super novice/amateur BMW chick so please forgive me for needing to ask which fuse(s) to check. I'll check the manual as well, but I want to make sure I check the one or ones related to the FSR (or climate control) if that makes a difference. Any advice? Thanks

2003 BMW 530i

There's a fuse that controls the blower motor, but it's in a godawful difficult place to get at. It's such a pain in the ass to find and get out that I almost think it's easier to replace the FSR first (though not cheaper).

The fuse is in a little two-fuse box up behind the glove box. You have to pull out the plastic cover under the glove box, open the glove box, then reach around behind it (you won't see it looking through the glove box). It's up about as far as you can possibly reach, and it's hard to even see it even if you lay on your back in the footwell and look up with a flashlight. I believe it's the rear fuse in this box (i.e., the one closest to you while pulling it out). Note that the fuses are upright in this box, which means you have to push/pull the fuse up even further to get it out, rather than pulling it down.

90%+ of the time, though, the problem is the FSR. If you're getting anything at all out of the vents, it's likely not the fuse.

ELVIS530i, this seems like a great post....sounds exactly like the problem i have....heaters never seem to switch on! and when i'm driving above 25mph i can feel little bit of air coming out of them...the faster i drive the more air seems to come out...thats maybe just the wind making the fans turn....but yeh then come the good times when he heaters start working, FOR A BIT...but if i;v been driving for a long time, they seem to come on abit more...but still seem possessed...

i drive a 1999 BMW 318Ci...anybody got any pics of what it looks like on a 318Ci??? hope its not too difficult/different....the dealer did say it was a long winded process....

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Many thanks for sharing this information with us.

I own a 2001 530i with 63K miles. A few months ago, I noticed strange behavior with the A/C and heater. Sometimes they work and sometimes they don't. When they work, I can't control the speed of the fan (but I was able to turn off the unit). The dealer (Stevens Creek BMW) asked $200 to replace a "controller" (they said if that does not fix the problem, they will replace the whole unit for $1,000+). I declined the dealer's offer to replace the controller and searched online about known problems with the A/C and heater - and I came across your article. After looking at your article and the photos, I was convinced that the problem will be resolved by replacing the FSU unit. So, per "domiguy" suggestion, I ordered the FSU unit from AutoHaus for $63, and replaced the unit per your instructions. Now I am able to control the fan.

While replacing the FSU, I found it difficult removing the wire and sliding the old FSU out, because of a cover right below the glove compartment. In your photo that says "follow the wires... FSU up there", I suggest you also show how to remove the cover below the glove compartment so that you have more room to work. I was not able to remove the cover, so I struggled to replace the unit.

Overall, your instructions are great. Many thanks once again.

Cheers!

Originally Posted by bimmer01

While replacing the FSU, I found it difficult removing the wire and sliding the old FSU out, because of a cover right below the glove compartment. In your photo that says "follow the wires... FSU up there", I suggest you also show how to remove the cover below the glove compartment so that you have more room to work. I was not able to remove the cover, so I struggled to replace the unit.

Here's the cover, looking up from the floor at the underside of the glove box:



Just grab the front of it and yank it straight back. It should come right out.

Elvis, just had to Thank You so much for your fantastic post on the FSU issue. I bought the part from BAVAUTO for $63 vs. $120 from the local dealer. BAVAUTO is my favorite place to get my Bimmer parts. Great service, quick delivery and Free Delivery to boot!

Anywhoo, I took my Grey Ghost to a local BMW mechanic, he wanted $80 for diagnosis. I waited and found your thread while searching the Web. I had posted on other Bimmer sites with no luck...

Was in and out of my car in less than 20 minutes!! Is the original part defective??? It resembles the cell phone from the early 80's compared to the new one!!

Thanks Elvis, you saved me and other some major bucks. UDAMAN!!

Thanks for the how-to.
my wife called my on the way home from school (teacher) and she said the heat wasn't working (2002 X5). i did a quick search on another forum, and it pointed me over here. so off to the stealership, $96 (OTD) & a little later, it was all fixed
if it wasn't winter, i would've ordered the part.

at least it was a real easy fixed compared to our Range Rover.

Thankyou so much for this post!
After 4 occasions this weekend where my battery had insufficient charge to start my e39, a quick search on bimmerfest gave me the solution.
£59.00 incl vat for the fsr, or hedgehog as my stealership referred to it as, and then reading ALL of the replies to your post, after I couldn't find the thing in the car (I'm a right hand drive and it's on the drivers side!!!) I'm all fixed

Many thanks

Ian
'02 520i

Elvis 530, thank you for saving me hundreds....hopefully. I went to my local mechanic and they quoted a ridiculous price saying that it was something difficult to get to. They even mentioned that they'd be replacing the fan motor. I just ordered the resistor from Autohaus so I'll keep you posted with the results following the replacement. Hopefully the motor isn't the problem.

Also, would this problem cause a parasitic draw from the battery? I had to have my 530 jump started on Sat. night, replaced the battery on Sun. only to find that the brand new Duralast 49DL was dead Tues. morning. I've got the car at the shop now and they're searching for what's causing the draw. I believe he stated that there were nearly 5 amps of draw. I took it in yesterday afternoon and they're still searching. I'm out roughly $500 for the investigation work and am wondering if any of you may have experienced something similar.

Help ASAP. Thanks.

Originally Posted by C Blood

Also, would this problem cause a parasitic draw from the battery?

Yes, that can happen. Sometimes the fan will keep running even after the car is off. It didn't happen to me, but I've heard of it happening to others.

Thanks for this info, its nice to see someone put all this good info together for other peeps. I just had to replace this relay on my 5 this last week (not knowing about this article) and I was skeptical of the advice given to me by a friend of mine with a 3, but he was right and 80 dollars later I have working climate control again!

Originally Posted by gaklager

Just replaced the Final Stage Resistor in my 2001 330 yesterday. It's quite a bit more difficult to get to this part in this version car. In my case, after removing the glove box, I had to remove the right footwell air vent. Behind the vent is a stepper motor that also needs to be removed, not too bad here just a linkage and couple screws. There are two screws on the resistor also and they're the same torx fastener as the stepper motor. Not that bad a job, 90 minutes or so. Blower motor no longer possessed!

I have 2001 325I and it was the exact same. Thanks guys for saving me big $$.

Hi there, my airco stopped working a few days ago. I can hit the airco button and it lights up. But the airflow from the vents doesn't change. So I started to search the net and came upon this post about the FSU and thought maybe i've the same problem because sometimes when i get into my car i can hear a little vent blowing behind the climate control unit (while the key isn't in the ignition). Not very hard though and always at the same speed. But it's not always there so maybe it's the same thing? Or should i bring it to a dealer to get the diagnose first?

Thanx Braz

I'm doing the install in the morning.. thanks Elvis!

no mention of taking out the lower black panel under the glovebox to give easier access to the area to be worked on.. how does it come out?

Okay, the black panel pulls straight out, it's got two white snap rails on the back, just tug it.

Man, I've got it done, but you almost have to be a contorsionist at my height to do this! Everyone wants to be tall, but when it come to fitting in tight spots, holy moly! It's done