abiazis

I have read several old threads on this, but still not very clear on what I should address......

Air from the outside of the car is coming in hot, like the heater is stuck on, through the right center and right passenger vents......cool air through the left and left center vents.....

Same condition when I turn the A/C on - cold on the left, warm air on the passenger side vents......

CC actuator valve issue a possibility?

I will research some more, but if anyone can assist with an explanation or previous experience as a fix, please let me know....

Thanks again for any insight.........

ToreB

Your mixer flap servo on the passenger side is defective and stuck in open position. Heated air comes from the engine permanently. There's two of these mixing servos, one for each side. They are supposed to move simultaneously.
It's a common fault, and the servo is fairly easy to change. It's located behind the kick carpet in the footwell. Have a look at my web page for details:
www.ccu.tore.bergvill.com
Cheers,
Tore

x50type

As ToreB says, your mixer flap servo [P/N 993 624 325 00] on the passenger side is defective and stuck in open position.

The cost of a new servo is about $260 from the dealer; fyi there are 5 on a 993.

The actual flap valve is not defective and the servo is attached to it by 3 screws, so the servo is easy to disconnect from flap valve.The good news is that it is a very easy job to change it yourself - dealer not needed.

Here's a photo [sorry its so big] of the flap valve in place and the servo controller innards. The pc board wears out and the fine spring connectors overheat. Unfortunately neither the board nor spring connector piece is available separately -surprise, surprise!

vanguard

I have those flap and servo for sale if you're interested.

abiazis

Thanks to all for the info, as I will further investigate today, etc.............

Vanguard can PM with a price if okay....

ToreB....great article...printed out for greater understanding...

X50 - thanks for photos and details.....

abiazis

Finally got around to removing the mixer flap servo motor on the passenger's side after testing to see if flap was working with thermostat - NOT.........flap was stuck on open allowing in the hot air all the time.........removed the servo motor for now..........thanks for all the advice....right on information..........

axl911

Anyone know how to test the servo on a bench? Mine is also stuck. Managed to clean the servo track and fingers, but don't know how to activate and test the motor function.

When I reconnected it back up, it doesn't move.

jo-hans

Last year I removed one servo from under the hood as it was not moving. I opened it up and tested the motor with a 9volt battery. Motor was fine. Then I noticed a brownish soldering connection on the PCB. I reheated that connection with my soldering iron and put it back together. Plugged it back in and it worked again.

ToreB

The servo can be tested on the bench, but must be done by applying 12V to the motor winding as well as measuring the resistance in the embedded potentiometer.
A stationary servo may also be due to an internal fault in the CCU. However, this is certainly possible to repair. Details in my previous post.
Cheers,
Tore

axl911

Do you know what pins out of the 6 pin connector?

abiazis

Finally got the new OEM servo motor from Sunset for $ 180 which was found most places for $ 250 and up. Took a week plus to get.....had it disconnected in the meantime........

Easy DIY repair and all HVAC in proper working order for summer......and next winter......

AC from all vents now instead of 2 driver's side only, as heat flap now operational and not stuck on open which brought the heat all the time...........thanks to all from Rennlist for the photos of the repair and diagnosis help............

Saved me at least $ 100 labor as the dealer/indie would have padded it.......plus aforementioned part savings from Sunset Porsche....)

osugasman

Andrew, I'm having the exact same problem. Anticipate the same solution. My questions for you are as follows:
1. When you pull back the kick carpet, is it obvious which 3 screws to remove to take the motor off the flap?
2. When the motor is off the flap, can the servo be left in the "closed" position for Summer driving?
3. Does the Sunset part include motor and flap or just motor?

--Brian

osugasman

Tore,

Would the T-OBD (that's in route from Norway as we speak) diagnose this for me? (The CCU fault vs servo fault)

--Brian

abiazis

Andrew, I'm having the exact same problem. Anticipate the same solution. My questions for you are as follows:
1. When you pull back the kick carpet, is it obvious which 3 screws to remove to take the motor off the flap?

Yes, pretty straight forward

2. When the motor is off the flap, can the servo be left in the "closed" position for Summer driving?

Yes, I did that for some time, but repair was so easy....you can close the flap with your hand and temporarily tape in place.....

3. Does the Sunset part include motor and flap or just motor?

Just the motor (for about $ 180 - best price anywhere) is needed to be attached to existing flap mechanism/tube.....also you can test the repair before reassembling the carpet, etc....by moving the thermostat on the climate control and watching the flap open and close....hope that helps....there are photos via search function on this site somewhere that gave me confidence to tackle the job.....took 10 minutes to complete....

95_993

Having the same problem on the drivers side. I will pull the kick panel and see what I can find.