Blower Motors Photos Heaters / AC

[jgurnari]

Like to know which Blower Motors are WHERE in my 1985 911 Carrera... Trying to figure out which are not working and where they are located and which levers and switchs they are connected to.
Ive looked at diagrams but cant tell. Does anyone have photos with descriptions/functions of each?
Thanks

[darrin]

on the heater side, the main blower motor is on the left side (facing forward) of the engine. In the cabin there are supplemental blowers behind panels in the sides of the footwell (driver's side cover's immediately to the left of the clutch pedal and passenger side cover's to the right of the passenger side footwell) -- heated air is routed just inside of door jam (inside rocker area by seat) from the engine compartment to the footwell blower) From the footwell blower, the heated air is directed up or down by the red lever on the dashboard. The fresh air and ac systems are both independent of the heating system (and each other). Hope this helps

[jgurnari]

do the supplemental blowers have motors? does the "dial", not the 2 levers, between the seats control the supplemental blowers?

[tratza]

Not to hijack this but where is the fuse to the footwell blowers. 1986 Targa but I assume (wrong) they are in the same spot. I've been told they are behind the glove box but I can't find them. Thanks all.

[darrin]

Originally Posted by jgurnari

do the supplemental blowers have motors? does the "dial", not the 2 levers, between the seats control the supplemental blowers?

the supplemental blowers (in the footwells) ARE motors -- the levers energize the motors (and act somewhat like a rheostat to control their speed) -- turning the dial to position 2 or 3 dramatically increases the speed of the footwell blowers -- position zero and 1 are the same -- all three of the heater blower motors are potential failure points -- further, there's a fail safe built in (a reed switch) that will prevent ANY blower motor from operating if the trunk-mounted blower fails.

[darrin]

Originally Posted by tratza

Not to hijack this but where is the fuse to the footwell blowers. 1986 Targa but I assume (wrong) they are in the same spot. I've been told they are behind the glove box but I can't find them. Thanks all.

on my June 1986 build, the fuses were affixed to the footwell blower motors themselves (they are newer blade-type fuses) -- believe that earlier 911s (including early build '86 911s) did not have fuses on/for the footwell blower motors.

[jgurnari]

Darrin
Should I assume that since none of the motors run I should start troubleshooting/ changing the main motor or under the rear lid?

[darrin]

Originally Posted by jgurnari

Darrin
Should I assume that since none of the motors run I should start troubleshooting/ changing the main motor or under the rear lid?

yes, I'd first check to see if it's getting power when the levers are up and then feed it power directly and see if it spins.

On my '86 a complete failure of my heater system was resolved through replacement of the main motor under the rear lid (and subsequent replacement of an annoyingly squeaky footwell motor before it spilled any"magic smoke")

[darrin]

there are a lot of threads to be found on our Carrera's heat -- here's one Help! Does anyone understand the footwell blower circuit?

[Hotshot]

Originally Posted by tratza

Not to hijack this but where is the fuse to the footwell blowers. 1986 Targa but I assume (wrong) they are in the same spot. I've been told they are behind the glove box but I can't find them. Thanks all.

Engine bay, but there not really fused per say. Most do a mod where you add a 10A blade fuse to the motor. The Eng compt has a blower switch fuse ( that I believe is it when I trace the circuit ) and the Eng compartment blower is next to it.

I’m doing this mod tomorrow actually on my 86.

The fuses didn’t show up till 88 according to my schematics. Everyone I’ve talked to says do it. As well to your front AC blower. Porsche sells a mod... it’s a blade and holder..

[Hotshot]

Originally Posted by darrin

yes, I'd first check to see if it's getting power when the levers are up and then feed it power directly and see if it spins.

On my '86 a complete failure of my heater system was resolved through replacement of the main motor under the rear lid (and subsequent replacement of an annoyingly squeaky footwell motor before it spilled any"magic smoke")

Also Darrin, once you fix that, here’s a good chance you don’t have a Pos 1 switch. I wrote a post on this with pics.

Pull out a floor blower and pull up on your heat leaver. At Zero pos. If it’s working it’s been modded. I can’t find that in the 86 Differences book but more than my can has it. Apparently pos 1 is so useless it’s rigged to work on O. Then 2-3 kick in.

86s have a lot of stuff different with them than most. Floor well heaters...

[Snitzler]

Originally Posted by darrin

on my June 1986 build, the fuses were affixed to the footwell blower motors themselves (they are newer blade-type fuses) -- believe that earlier 911s (including early build '86 911s) did not have fuses on/for the footwell blower motors.

1988 3.2 Coupe, passenger side. Driver side is similar.

[Hotshot]

Thx for that pic, now I know how to do mine. Ya only the 88 diagrams have the fuses.

[HaroldMHedge]

Originally Posted by jgurnari

Like to know which Blower Motors are WHERE in my 1985 911 Carrera... Trying to figure out which are not working and where they are located and which levers and switchs they are connected to.
Ive looked at diagrams but cant tell. Does anyone have photos with descriptions/functions of each?
Thanks

The Bentley Service manual has a good listing of all of the blower motors in the electrical section and provides a decent explanation on their operation and trouble shooting in the HVAC section.

Concerning the footwell blowers:
TSB 8704 Fuses for Additional Heater Fans indicates these were installed from production date April 23, 1986.

VIN 91 0GS 12 1913
91 1GS 16 1516
91 6GS 17 1217
93 1GS 05 1081

The fuse is part no. N 017 13 15

You should add these fuses if this upgrade has not been performed.

[Hotshot]

Originally Posted by HaroldMHedge

The Bentley Service manual has a good listing of all of the blower motors in the electrical section and provides a decent explanation on their operation and trouble shooting in the HVAC section.

Concerning the footwell blowers:
TSB 8704 Fuses for Additional Heater Fans indicates these were installed from production date April 23, 1986.

VIN 91 0GS 12 1913
91 1GS 16 1516
91 6GS 17 1217
93 1GS 05 1081

The fuse is part no. N 017 13 15

You should add these fuses if this upgrade has not been performed.

Any chance I can get a copy of that TSB? I have the Teknik one and it mentions nothing on that. My shop manual only shows the schematic on the 88. Even 87 doesn’t have it.

Also, For my Targa Bentley is wrong about the window tracks. That was in the Teknik Bulletin..

[HaroldMHedge]

Here's the requested TSB and an additional one on repairing the fans.

TSB 8704 Fuses for Additional Heater Fans



TSB 8706 Repairing Additional Fans

[Hotshot]

And you are awesome! Thx. I have the 86 main changes page overview.

[speedracer92]

Might help some

[Jack Stands]

When compared with the original heat exchanger design, this must be the most convoluted kludge I’ve ever imagined Porsche could have designed. If you needed more heat or defrost originally, you could simply shift down a gear to increase output from the engine fan. Simple, elegant, and no additional circuits to troubleshoot!

[Nick Triesch]

Why does such a tiny car have so many blowers?? Holy cow! My 66 bug had forced air and the heat would blast you out of the car!! I think maybe two motors would have been enough .