Final stage unit failing? Can you repair it? - BMW Forum

jroberts312 · 06-15-2004, 02:09 PM

My a/c will not go past medium speed. It sometimes goes on high then back down. I have read that it is the final stage unit. Can you repair this part? Where is the replacement part sold the cheapest?

BenRaty · 06-15-2004, 05:19 PM

Sadly, the AC/Final Stage happens to be one of the weak-links in the E36 line. Mine degenerated to the point that it would arbitrarily shut itself off frequently, and there was nothing I could do to turn it back on but wait an indeterminate amount of time.

You can either have the entire unit replaced by your local BMW dealership, find a used (and hopefully repaired/upgraded) model for sale, or pay an electronics technician to repair it. I ultimately bought a refurbished unit, and it has performed correctly so far.

jroberts312 · 06-18-2004, 02:50 PM

Replaced the final stage and now the ac works fine. My question is can you not repair the old one? $120 bucks is expensive and as much as they seem to fail, it would be nice to repair somehow. Has anyone tried?

BlantonG13 · 06-18-2004, 03:18 PM

what exactly is the final stage unit? Is that the digital control unit on the Dash? Mine is doing the exact same thing and it is now 90-something degrees outside, and its been raining a whole lot

jroberts312 · 06-18-2004, 03:22 PM

The final stage unit (or also called final stage resistor pack) controls the speed of the blower. Mine was blowing only half way. Just replace it and it will work just fine. Bought mine yesterday and installed the same night in 45 minutes. On my 97 318I it is located above the gas pedal to right. Working fine. If you are having problem with the display then that is a different matter. What problems are you having exactly?

RallyE36 · 06-18-2004, 03:39 PM

The final stage resistor looks like a sealed unit. There are no external screws/bolts on it to take it apart.
For $127 CDN it was worth it for me to just replace it. Now it works as it should.
The dealer will have plenty in stock as these are a "weak link" in the E36 .... hmmmm ... I wonder if there made by Lucas .... nahhhh .... a Bimmer will never have British parts in it.

Eraj · 06-29-2004, 11:36 AM

Hi Guys,
I have a 320i - '94. Guess what, the resistor pack is nowhere near the gas pedal. I took the panels out from both sides, and still nothing. I've seen a picture of the resisitor, so had a fair idea of what to look for.

My blower motor does not work on position 1, but is okay on 2-4. Could this be anywhere else?, like higher up under the dash? Has anyone done this on a 320 and not a 325?

Any help is appreciated guys.

Thanks

BlantonG13 · 06-29-2004, 11:55 AM

The problem with mine, is the Climate Control digital control module on the dash, just under the radio. This thing is a piece of shit. From what I have heard around the net, this is also a pretty weak link in 96-older BMWs. I pulled it out of the dash and played around with the wires and everytime I mess with the connection, it will turn back on. Moments later, it turns back off. Sometimes just the display will turn off and on, leaving the blower going. I just bought a used one off ebay because I have seen where these things can cost upwards of $400 at the dealer. I am not wasting my hard earned money on that right now...

97alpineM3 · 06-29-2004, 04:03 PM

You could always roll the windows down... and take your a/c out...... its pretty heavy too..... I did....

Eraj · 07-06-2004, 12:45 PM

Hi,

I replaced the resistor pack last week. Cost me only $33 at the stealer, works fine now.

Thanks

badaxe · 07-16-2004, 02:51 PM

I have a 2000 323it and am experience a similar problem with the blower unit. I confirmed that the a/c unit is engaging under the hood, but the blower only kicks on for a couple minutes once in a blue moon. After reading your forum, I'm convinced that it is a problem with the final stage resistor. Does anyone know if this seemingly common problem with the E36 series was passed onto the E46 series? If anyone has any knowledge on this subject it would be greatly appreciated. Have not yet located the final stage resistor unit under the dash so anyone with knowlege of it's location would also be appreciated. I plan to pick up a unit and replace it myself rather than put myself. Thanks in advance.

RallyE36 · 07-16-2004, 03:03 PM

The E46 series has been around for a few years now, so the dealers should have a pretty good history of problem areas, including the final stage resistor being a "weak link". They should also be able to tell you where it is in the E46.

As for repairing an existing resistor, by the time you pay a technician for his time I don't think you'll be any better off. You'll still have a used one at the end of the day.

Turbodefrost · 07-16-2004, 03:48 PM

Just move to Northwest Washington. B) No need for A/C there!

98e36bostonchic · 11-10-2004, 10:41 PM

I'm a 23 yr old girl in boston, and suffered this summer with no ac due to the same issue as you guys are having. can anyone e-mail me a pic of the resistor pack?
Also I had the dealership install an aftermarket radio with cd when I bought the car,3 months into the summer when my climate control (resistor pack I think) went, my cd player went too. I went and bought a new cd player and still nothing, thought it was the radio, can anyone help me?