3.2 Carrera heater question

[gar]

So I've replaced the blower motor and hooked it up, turned the car on, pulled the handles and....

nothing.

What else should I check to figure out what the problem is?

I don't have the footwell blower motor switch hooked up at the moment (in the console that sits between the seats), would that in some way prevent the engine compartment blower motor from coming on?

[Rick Lee]

See if your flapper boxes are stuck shut and inspect their cables. They wear out often.

[gar]

Well, I know the boxes open, because I can get heat to enter the car. Can the boxes open but not have the circuit complete?

Other suggestions?

[Rick Lee]

Did you go back to listen to the blower motor? I rode in a 993 the other night with the blower removed and it heated just fine without it. So are you sure the blower is working? also see if the heater hoses are both secured to the heat exchangers.

[Dan Owens]

I'm a little confused by what you're asking. The handles on the console only turn the foot/wheel well blowers motors on, not the engine compartment blower motor. If you don't have the console switch hooked up to the footwell blowers they won't work when you lift the handles. I'm not sure if that's a separate circuit for the engine compartment blower or not. I believe, but am not sure, the engine blower is on a separate relay. Which blower motor are you trying to get working, engine or foot well?

[gar]

I'm trying to get the engine one working. It's a brand new unit, and all the hoses are secure. I don't get any flow of air from the motor at all, and there's no sound, so I think it's safe to assume it's not getting power.

I was thinking that maybe since the footwell blowers don't work unless the blower motor is turned on, that by not having the footwell blower switch hooked up, it would somehow interrupt the circut for the engine compartment blower.

[Dan Owens]

Okay, That's what I thought you were tryin to do. I'd hook up the switch to complete that circuit and also check the engine blower to see if it's getting power.

[aj88cab]

Originally posted by gar

I don't have the footwell blower motor switch hooked up at the moment (in the console that sits between the seats), would that in some way prevent the engine compartment blower motor from coming on?

How did you disconnect the footwell blowers? Did you perhaps disconnect the engine blower contacts on the red levers instead? And sorry, but I got to ask....did you reattach the plug to the engine blower fan. Are you getting power to the blower connector at the fan. If not check fuses (in engine compartment) and the blower control relay (also in engine comparment) .

Here are a couple of related threads that might shed some light on this mysterious control circuit:

Footwell Blowers

Let me up, I’ve had enough…

http://www.porschenet.com/bruns02.html

http://forums.rennlist.com/rennforums/showthread.php?t=122716

Good Luck (and you'll need it on this one )
Andrew

[gar]

Well, everything is connected EXCEPT for the console with the dial for the footwell blowers.

I'm going to try connecting that tonight and see what happens. It'd also help if my voltometor (sp?) actually worked!

[fuelie600]

Originally posted by Dan Owens
The handles on the console only turn the foot/wheel well blowers motors on, not the engine compartment blower motor.

Dan, you might want to make sure your rear motor works.

The handles definitely turn on the engine compartment blower. (at least on an 87 with manual climate control.) There is a micro switch under each lever that turns it on. You might want to clean the switches. When I got my car, the drivers side switch had carpet fuzz in it and it wouldn't make contact. The passenger side was ok.

The footwell blowers are turned on by the rotary knob after the lever switches are on.

[gar]

Well I checked, and there's no power going to the wiring in the engine compartment. Next step is to try to try to figure out where the circuit is disrupted.

[masraum]

Don't forget the $100+ relay that's in the engine compartment. That relay is setup so that if some of the system doesn't work none of it will. The Footwell blowers and the engine blower all have to be functional.

[gar]

What's the best way to check the relay? Remove it from the car?

[aj88cab]

Beg, borrow, or steal a good one and try it in the car. That is the only way I know to be sure. This is not a simple relay it has a small PCB in there with a couple of relays with series and parallel contacts, a couple of inputs, and other electronic goodies. Read the "bruns02" link above if you haven't to see just how convoluted this control circuit is.

[rcaradimos]

Footwell booster motors go on with engine compartment blower motor, low speed, both sides no matter of lever you lift up and the speed is operated with dial between levers. Both sides of footwell booster motors on my 87 had the rat cage binding and each of there fuses burnt out, engine compartment motor worked fine, the fix was remove motor 4 c clips and wire harness plug. Take off cap of motor one screw. grip top shaft with vise grips and slowly turn rat cage counter clockwise just to stop binding oil and grease top felt oil pads, replace burnt fuse, put cap back on, plug in wire harness power up engine compartment blower while holding boster motor, it should fire up try speed control switch if all good then reinstall.