9-5 heater fan problems?

The heater fan on my '99 9-5 SE (2.3l LPT) has gone intermittant - as
in, usually doesn't run. When it runs it runs full speed, when it
doesn't, I get a VERY low trickle of air from the vents I select.

I can use the ACC to change from floor to dash to windshield, and I can
hear the servos clicking and the little bit of air does go where I tell
it. My temperature gage is behaving normally and I have sufficient
coolant. The air that comes out is warm, but there's very little of it.

The ACC does respond normally to me setting the fan to level 1-8 (or
however many bars are on the graph for that) - but, the fan doesn't
acutally speed up.

When it works, the fan starts out kind of growly-sounding. To me, I'm
thinking the fan is going south but, what's the track record of this?
Does this failure mode point more to the fan, or to the controller? All
the fuses are OK, and I've swapped relays around with no change in
behavior.

Thanks,
Dave Hinz

On 11 Dec 2007 02:04:07 GMT, Dave Hinz <DaveHinz RemoveThis @gmail.com> wrote:

>The heater fan on my '99 9-5 SE (2.3l LPT) has gone intermittant - as
>in, usually doesn't run. When it runs it runs full speed, when it
>doesn't, I get a VERY low trickle of air from the vents I select.
>
>I can use the ACC to change from floor to dash to windshield, and I can
>hear the servos clicking and the little bit of air does go where I tell
>it. My temperature gage is behaving normally and I have sufficient
>coolant. The air that comes out is warm, but there's very little of it.
>
>The ACC does respond normally to me setting the fan to level 1-8 (or
>however many bars are on the graph for that) - but, the fan doesn't
>acutally speed up.
>
>When it works, the fan starts out kind of growly-sounding. To me, I'm
>thinking the fan is going south but, what's the track record of this?
>Does this failure mode point more to the fan, or to the controller? All
>the fuses are OK, and I've swapped relays around with no change in
>behavior.
>

It could be either, I guess. The controller failed on mine a while
back, with different symptoms. The fan went to full speed constantly,
even with the ignition key out. Yours would still be a plausible
controller failure though.

It's worth checking the current through the fan fuse as you adjust the
speed. If the current is sensible, or on the high side, then my money
would be on the fan. Otherwise it would be the wiring, or the
controller.

You could also check the control voltage from the ACC unit. It goes in
on pin 8 of the speed controller connector. It's 0V for off, rising to
5V for max speed - assuming the 9-5 is the same as the 9-3.

Cheers,

Colin.