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[email protected][_2_] trader4@optonline.net[_2_] is offline
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Default Root cause insight into the common BMW blower motor resistor failures

On Mar 21, 8:08*pm, wrote:
On Thu, 21 Mar 2013 22:54:59 +0000 (UTC), Bimmer Owner

wrote:
On Thu, 21 Mar 2013 15:03:45 -0700, Ashton Crusher wrote:


If it's being blown by intermittent high current draws the
fuse could protect the $100 FSU.


That's an interesting idea. The FSU supposedly consumes the
most power when the blower motor is set to the LOW settings
(simply because it has to dissipate the power as heat), so,
we could prevent excess current by fusing... say with a 10A
fuse, the blower motor (which is said to consume 5 to 6 A).


* So the crafty germans are using a high tech solid state resistor
instead of a PWM speed controller???

If I had one and it blew I think I'd be designing a PWM controller to
take it's place. *Need to find out what kind of signal the controller
expects, but that shouldn't be too difficult.


The dopes at BMW aren't any better at PWM's either.
They use a PWM signal to control the aux fan on the radiator.
You, know, the one that comes on if the cooling temp gets
too high or the AC is on, etc. Apparently just a simple on/off
motor wasn't good enough. So they made another one of
their German electronic miracle gadgets that's part of the
fan motor. That's right, electronics sitting right next to the
hot radiator.....

On the TV show All in The Family, the meathead was arguing
about Nixon and Watergate with Archie. Archie told the meathead
that Nixon's mistake was when it involved electronics, ie bugging,
taping, etc, that he should have used the Japanese, not Germans,
ie Haldeman, Ehrlichman, etc. I think Archie was on to something.