1995 BMW 740 Intermittent A/C

1995 BMW 740
118,000 MILES • V8 • 2WD • AUTOMATIC
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GRADY_TX
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The subject is not quite accurate. The A/C works fine. What is intermittent is the blower.
It makes no bad noises, it always works in the morning or after a good rest; it just sometimes doesn't work on a re-start.
Mostly it will not work until the car sits for an hour or two. Occasionally it comes on after a 10-15 minutes of driving.
Turning the a/c switch and other controls on-off has no effect.
When off, a small amount of cold air still seeps through. The compressor clutch cycles on and off about every 30 seconds.
Yet I think it's a s sensor or switch rather than the entire blower (fingers crossed). Grady
Jun 24, 2010 at 8:32 PM
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DOCHAGERTY
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The final stage unit sits on top of the fan, and it is suspect.
Jun 25, 2010 at 12:10 AM
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GRADY_TX
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My book doesn't show a "final stage". It does refer to a power unit (which iItake to be the blower motor) are they the same or am I missing something?

Either way I assume access it via removing the air bag, dash, etc. Not sure I have the courage for that! What is the shop time to make the change?

Thanks Grady
Jun 25, 2010 at 8:30 AM
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GRADY_TX
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Nothing in the Bentley Book but lots of info on the internet. Appears to be a small electronic unit in the pass. foot-well and a easy change out.

I'll give a try thanks! Grady
Jun 25, 2010 at 9:04 AM
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DOCHAGERTY
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Did the problem get taken care of Grady?
Jul 7, 2010 at 11:31 PM
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GRADY_TX
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Not really - Turns out the easy-to-change version is only for 3 & 5 series, on a '95 7 series it's buried in the blower motor so it's a full-dash apart job to replace it.

The good news is that with a can of refrigerant, the a/c is cold enough to keep the module from overheating (I'm guessing).

Knock on wood, it has been working.

Thanks for checking. Grady
Jul 14, 2010 at 8:07 PM
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DOCHAGERTY
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Kool baby
Jul 15, 2010 at 9:25 AM