Vent/defrost Controls...

[Mitch Leland]

Howdy,

My fresh air vent motor doesn't work, I've installed a new vent motor and it works with direct temp power. The 4 prong female plug has one hot terminal (it's hot even with the switch in the off position), but the other 3 do nothing. None go to ground. Should one of the plug terminals go to ground?

How do you remove the frame and three levers from the dash? I want to inspect the switch on the back side that controls the vent blower motor.

Thanks,

[tcar]

Do you have A/C?

[Mitch Leland]

TCAR: Thanks for your inquiry. Yes I have A/C. Miraculously the blower now works. I replaced the motor with a new one, (the old turns out did work after I had already received the new one and removing the old one from the housing). But the interesting thing is I didn't get it to work until I removed the 4 prong plug from the blower housing. When I put power to it again the motor worked.

I think the overload contacts closed and did not open after cooling off. In the housing and as part of the 4 prong plug are two resistor springs that when they get hot contract and close a set of points. I'm not sure how all this works, but when the plug was removed and powered up the motor worked on the bench.

Yippeeee...

[tcar]

I'll try that. Mine doesn't work either.

I asked about A/C, because I have 3 levers too, and it looks like I should have 4. The top lever only moves 1/2 way (left half).

[MattAlpha]

tcar,

That top left lever controls the mixture of cabin air to fresh (outside) air that is circulated through your cabin. All the way to the left is cabin air only. All the way to the right (half way on the panel) is all fresh air. The lever to the right controls the 3 speeds for the fresh air blower (Slow, medium and fast). If its in the middle position on the panel (full left portion of its travel), then the blower motor is in the off position.

You should have a separate rotorary switch in you center console to control the motor for you're A/C.

Hope this helps,
Matt

[tcar]

My A/C is fine and works, all on the console.

My question is that I only have the left lever on the top. It works and moves freely in the left half of the channel. There is no right lever in the top channel, so I don't even know if the blower fan works.

I have to use A/C to get any ventilation at all.

[Mitch Leland]

TCAR, The top lever which operates the 3 speed fan does move very freely, nearly as if it wasn't hook to anything. However after getting my blower to work I guess that's the way it is. When the top lever is at the full left position, it's off. As you move it to the right you should get three different speeds. Even when my vent blower motor didn't work the fan icon of the left side of the control panel lit up as you moved the top lever to the right.

Just the blower motor will cost you about $100.00 and 3-4 hours of work . You should have the Bently's Manual to guide you through the process. When you get you motor you'll have to remove the plastic squirrel cage blower and install it on the new motor. I can give you some suggestions to accomplish this if you like.

I had some great help from another member, it's a small motor doing a big job so there's every reason to think you'll need a new blower motor. The only thing I did was to order the motor before removing the old one. The old one turned out to be OK.

You should put a test light on the incoming female plug to see if you have power to the motor before taking everything it apart. I believe the power lead is the bottom female receptacle on the right side (the right side of the car). In my case I believe my problem was with the resistors inside the vent housing because I had power, but the blower motor didn't work.

I just got my car in March and found the A/C, heating and fresh air systems to be different from any other cars that I've had. You basically have three independent systems with no overlap. Each system has it's own controls

Good luck,

[tcar]

Thanks, but the problem I have is that I don't even have a lever to operate the blower.

[MattAlpha]

tcar,

Have you checked with a flashlight to see if the linkage is in there for the blower motor control lever? It might have broken off, or someone removed it.

Do you notice a difference when you move the "air mixer" lever back and forth, i.e. do you get fresh into the cabin when the A/C is on and if you slide it to the left do you only re-cycle cabin air?

-Matt

[Mitch Leland]

TCAR,

Whooops... Bad, Bad... If you radio comes out easy you might remove it to look at the back of the vent control panel. You might have to use a mirror, but it might give you better access than from underneath.

I had posted a thread asking how that control panel comes out, but I didn't get any feed back.

[tcar]

I saw that thread, was hoping someone would answer.

Looked w/ a trouble light, but can't tell. Actually doesn't look like there's another lever in there. Guess I'll get out the Bentley manual and go in thru the trunk.

[tcar]

Fixed the problem. Got out my Bentley. Turns out the bowden cable in the trunk by the blower motor was not adjusted correctly.

Adjusted it and now the blower works as supposed to.

With A/C cars, though, you only get outside air from the blower on you feet and the defrost vents.

Without operable vent windows, that means the A/C is the ONLY way to get some air on a hot day.