Jump to content
×
×

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)
MHD993

993 Climate Control Unit

Recommended Posts

The climate control unit on my 95 993 isn't working properly. When either the A/C, max A/C or recirculating buttons are pressed, the fan ceases in the cockpit after about 2 seconds (but a fan noise can still be heard coming from inside the dash). When the A/C or max A/C buttons are depressed (released), the fan begins blowing again and cold air can be felt for a moment or two. Accordingly, it appears that the CCU is shutting down interior (to the dash) vents?? when these buttons are pressed. My local dealer estimates a replacement CCU to be in the neighborhood of $1k + labor. I have noticed a few sites selling remanufactured CCUs, but I'm worried I may be paying for someone else's problem. Does anyone have any advice regarding this type of issue?

Thank you.

Share this post


Link to post
Share on other sites
    You can remove these ads by becoming a Contributing Member.

The climate control unit on my 95 993 isn't working properly. When either the A/C, max A/C or recirculating buttons are pressed, the fan ceases in the cockpit after about 2 seconds (but a fan noise can still be heard coming from inside the dash). When the A/C or max A/C buttons are depressed (released), the fan begins blowing again and cold air can be felt for a moment or two. Accordingly, it appears that the CCU is shutting down interior (to the dash) vents?? when these buttons are pressed. My local dealer estimates a replacement CCU to be in the neighborhood of $1k + labor. I have noticed a few sites selling remanufactured CCUs, but I'm worried I may be paying for someone else's problem. Does anyone have any advice regarding this type of issue?

Thank you.

I'm curious how you resolved this issue. I realize this is an old post but I'm having the same problem in my 993 now and have been debating the merits of buying a $300 used unit instead of a $1000 reconditioned unit.

I'm also curious if this is a common problem on 993s.. Do these things just tend to go bad after a while? If so I'd rather shy away from a used unit. It seems like there are a lot of them for sale out there so there must be a demand for them.

Anyone else have experience with this?

Share this post


Link to post
Share on other sites

I first asked my Porsche shop to verify the problem was with the CCU and not with the relays. Once verified (hooked up a functioning CCU and all was well), I debated the merits of used versus reconditioned. Ultimately, I chose reconditioned (ie. warranty). And it did cost around $1k! If the issue were to occur again, I might try a used unit (as long at I could return it if it didn't work). On a related subject, the winter prior to the failure was the only time I had stored the car with a "battery manager" attached. I'm unsure if the two are related, but the car came out of storage with a non-functional CCU. As for this being a common fault, I agree ... there seem to be a lot of used CCUs on the market. However, I had several "experts" tell me these things are "bullet-proof" ... go figure.

Share this post


Link to post
Share on other sites

I ended up taking mine apart and fixing it. It seems to work fine now. Mostly it looks like there was some residue on some of the components that needed cleaning up. I suspect this might be caused by a damp environment, but it's hard to be sure.

Anyway, I'm a happy camper and saved myself a load of cash..

Share this post


Link to post
Share on other sites
I ended up taking mine apart and fixing it. It seems to work fine now. Mostly it looks like there was some residue on some of the components that needed cleaning up. I suspect this might be caused by a damp environment, but it's hard to be sure.

Anyway, I'm a happy camper and saved myself a load of cash..

Hi,

I have the same problem with my 993. I would like to know you accessed the aircon CCU and cleaned it.

I would appreciate your help.

best regards,

George

993 coupe 1995

Share this post


Link to post
Share on other sites
I ended up taking mine apart and fixing it. It seems to work fine now. Mostly it looks like there was some residue on some of the components that needed cleaning up. I suspect this might be caused by a damp environment, but it's hard to be sure.

Anyway, I'm a happy camper and saved myself a load of cash..

I think my CCU is malfunctioning but I do not want to buy a new one since this problem just occured out of the blue. I would appreciate any tips on removal of the aircon CCU and cleaning of the same device.

Share this post


Link to post
Share on other sites

I know this is an old topic - but i am having problems, 

My CCU is not working full stop.
It is dead.
I plan to remove it soon to see if I can fix it, but in the meantime, here are a couple of related links:

https://rennlist.com/forums/964-1989-1994-911/687307-ccu-button-replacement.html
https://www.bergvillfx.com/ccurepair

https://rennlist.com/forums/993-forum/950555-hvac-unit-dead-trouble-shooting-check-list.html

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.