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'93 850 heater fan works on 4, not on 1, 2 or 3!

For a while now, the heater fan on my '93 850 SE 2.0 20v saloon has been playing up. Half the time it would work fine, then for the rest would generate a quite loud noise when rotating. Not a squeak, more of a roar! Sometimes, it would swap between these quiet and loud modes at random moments (accompanied by a loud clunk when it did so).

Then two weeks ago, the fan stopped working altogether on settings 1,

2 and 3 but DOES still rotate on setting 4 -- but now the roaring noise is there permanently.

Following advice given elsewhere in this group, I've just changed the associated relay, but to no avail.

So what now? The switch? The fan itself? I've checked all the connections and they appear to be in order.

Another post suggest changing the associated resistor, but I'm having difficulty locating it. On later models it appears to be underneath the relay, but doesn't appear to be so on my car! Any ideas?

TIA,

Stu C

Reply to
Stuart Cormie
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You've burned out that resistor, it drops voltage to the motor on speeds

1-3, and is not used on speed 4 where the motor gets full voltage. And you need a heater motor to take care of the clunking and roaring. The resistor is a "home plate" shaped thing with a 4 pin plug in the heater box right beside the heater motor.
Reply to
Mike F

Thanks for the info. Both resistor and motor replaced (the latter a breaker's yard unit), and now all is dandy.

Removing the old motor, I did find a large piece (3" x 3" x 1") of a stiff foam-like material lying in the space where the fan was, that had obviously broken off from somewhere. Maybe it was this that had been doing all the clunking? Just a thought.

Cheers,

Stu C

Reply to
Stuart Cormie

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