I think it's already been suggested, but if the car were my own vehicle, I'd
be content with a multi-position switch for the blower motor.. this is a
very reliable method.

A heavy duty switch and some over-rated power resistors would likely outlast
many replacement OEM miracle-in-a-box modules.

The parts, wire, a cover for the hole where the original removed module was,
and a Saturday afternoon would likely cover the cost investment.

I'm fairly certain that there are off-the-shelf variable speed modules that
would be an adequate replacement for an automotive blower motor application.

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Cheers,
WB
..............


"jim beam" wrote in message
...

you don't need to know this stuff any more than you need to know the gas
excitation voltage in a broken fluorescent tube. because you're not going
to unpot the thing and replace the chip. because it's probably not the
chip in the first place.

not trying to be rude - just trying to get you focused on the relevant
stuff - that the two options a

1. continue replacing the existing [under-rated, low tech] unit.
2. build and deploy a pwm unit instead.

#1 is really not /that/ expensive, particularly if you factor in time,
even if it is part of the bmw marketing susceptibility tax.

#2 is a much better time investment - it certainly has a much better
return than figuring out that the existing unit is not repairable later
rather than sooner.


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fact check required