Any idea why my fan doesn't work?

[s1oww]

My 84's front de-misting fan doesn't work. Is there a common problem I should look for? It all looks connected, I've checked the fuses yet still nothing. Before I take it apart I wondered if anyone here knows of a common problem?

[pete3799]

They self destruct quite frequently.
Do a search for "fresh air blower"

[wwest]

De-misting MUST involve lowering the relative humidity of the cabin atmosphere, specifically that at the surface of the windshield or flowing across same.

In most cases that involves HEATING the cabin atmosphere to lower the Rh, relative humidity, and/or lowering the windows slightly in order to more quickly PURGE the high humidity cabin atmosphere.

FORCED fresh inlet airflow AND OUTLET AIRFLOW will abate the rise in cabin Rh due to human metabolism thereby significantly lowering the onset of interior windshield surface fogging.

But once condensation has formed, or begins to form.......HEAT!

And let's not have some I@#%$ suggest using the A/C, the A/C in our 911's is ALWAYS in recirculate mode, plus, BIG PLUS, mother nature may not be in the mood to be co-operative.

Oh, the only time I have even been tempted to use the fresh air blower in my 78 Targa is with top on as a shade from a hot Kansas sun at mid-day. Don't think that I have ever considered using it at all in climatic conditions conducive to windshield fogging.

[wwest]

Originally Posted by s1oww

My 84's front de-misting fan doesn't work. Is there a common problem I should look for? It all looks connected, I've checked the fuses yet still nothing. Before I take it apart I wondered if anyone here knows of a common problem?

More direct answer...

Yes, VERY common failure, mostly results in loud squealing as the bearings begin drying out. Had I known at the time when mine was complaining loudly how useless it would prove to be I would have simply disconnected it rather than DIY repair.

Perhaps that's what your previous owner did?

[DBDP]

Just to be the I@#%$ as noted above, one of the attributes of air conditioning is dehumidifying especially when no new humid air is being introduced(recirculated air).

[Ronnie's.930]

Originally Posted by DBDP

Just to be the I@#%$ as noted above, one of the attributes of air conditioning is dehumidifying especially when no new humid air is being introduced(recirculated air).

Not to worry, wwest has proven time and again to be quite skilled in the art of being an I@#%$!!!

[wwest]

Originally Posted by DBDP

Just to be the I@#%$ as noted above, one of the attributes of air conditioning is dehumidifying especially when no new humid air is being introduced(recirculated air).

Have to ask...

Just how well is that 2011 F-150 EcoBUST working out in our climate?

[lawereyanlu]

In most cases that involves HEATING the cabin atmosphere to lower the Rh

[s1oww]

I found it useful in my old targa and it was annoying when it didn't work in my coupe. When i move the slider it does nothing at all. Is there a common place they get disconnected?

[javadog]

Assuming you have no blown fuses... There is a connector in the bulkhead between the interior of the car and the trunk. Follow the wires from the ventilation controls to find it. If all is well there, you probably need to get a wiring diagram, a multimeter and have a look at the blower motor.

JR

[Porchcar guy]

Hey wwest..did you take your medication today or are you practicing using big words :=)

[86 911 Targa]

I agree with javadog, here's the ckt for your car.

Good luck,

Gerry

pm me as needed.

[jfort]

I need to remove the fresh air blower motor from a 77 930. Anything I should know if advance? Hard to do?

[javadog]

It's just like any 911. Not hard to do, just a little time consuming. There a a zillion threads already, so a search might be helpful.

This thread has some info that might help, towards the end:

Retrofitting non-A/C ventilation ducts

JR

[jfort]

looks like you take the clips off that hold the two halves of the housing together. found the motor for $85 using a thread from another PP thread. hope to get at it this week end. thanks for the response

[jfort]

You're the man, javadog. It looks like the instruction I needed to remove the fresh air blower is on page 4 of your referenced thread. Wish me luck.

[javadog]

I wish you luck. It's not all that hard. Just don't let any of the little rings fly off into a dark corner.

JR