AC Blower motor failure

I have an E39 528iT. It is an American market car with the dual zone HVAC controls. When I start it with the A/C on (hot humid climate) the blower will run porperly for about 2-3 minutes, and then suddenly stop
for 2-3 minutes. It will continue this cycle ad infinitum. The A/C coil is still cold, you can drive the car with the back windows cracked down at speed, and the vent system will draw in chilled air from the outside through the chiller coil. The problem is totally independent of any setting in the HVAC control head. Anybody got an idea?
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Frost wrote:

So a GOOGLE on "final stage" or "final stage resistor" - or just go to the dealer and get one. Takes about 15 minutes to install. It's located behind the carpeted panel on the right side of the console/tunnel.
Very common problem... the new one has been "improved" and hopefully won't fail as often.
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dmin wrote:

Wow! I was just ready to post a thread with the same problem on my 99 M3.
The fan will shut down for a couple of minutes and then return to work properly. When it's 110 degrees Farenheit inside the car that's no fun.
Is that part you describe for the e39 the same for the e36?
David H.
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dmin wrote:

Wow! I was just ready to post a thread with the same problem on my 99 M3.
The fan will shut down for a couple of minutes and then return to work properly. When it's 110 degrees Farenheit inside the car that's no fun.
Is that part you describe for the e39 the same for the e36?
David H.
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Maybe the part is not exactly the same but it performs the same function. The final stage is nothing more than a fancy resistor circuit like the one used in other cars, is just that the BMW part is very poorly designed and more expensive than normal. I had the "final stage" replaced this week on our E46.
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No - in your case the HVAC control unit is bollixed up. Do a search on Ebay for E36 HVAC, or go to any E36 forum and do a search. Very common failure. Fixing it requires some soldering skills - you have to replace a capacitor on the board of the HVAC control. Or replace the entire control unit ($$$$$)..
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admin wrote:

Or the problem could be that notoriously bad capacitor (rated 47 micro Farad) on the circuit board. There used to be a great site that some guy put up that gave clear instructions with pictures on where it was, how to get to it, and how to replace it.
I went to Radio Shack, bought the $2 capacitor, some electronics- grade solder, and did the job myself. No problems at all since! Who knows what a dealership or shop would've charged to fix the simple and cheap problem; I'd guess many hundreds of $, based on experience.
I just found the link and it's dead. Too bad. There are prob. others, as this is such a common problem. The guys should do a little searching.
----- Kill ratio of Palestinian children to Israeli children 5.7-to-1, Israel's favor. Kill ratio of all Palestinians to Israelis: over 3-to-1. --------- http://www.lrb.co.uk/v28/n06/print/mear01_.html ---------- "Don't worry about American pressure on Israel. We, the Jewish people, control America, and the Americans know it." ---Israeli Prime Minister Ariel Sharon, 2001
--
Cliff


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