burgass

Hello
Does anybody know where in Europe I can get my CCU repaired. My mechanic says I need a new one but the price is a bit high IMHO.
Regards

kennyjr748

Hi burgass-

I also had problems with my ccu. The HVAC fan would not stop running which would cause my battery to drain. There is a place in the states that fixes the units for about $300 US. I lucked out- I removed my unit, unplugged it and simply plugged it back in after a couple of minutes. I'm not sure what that did- but the HVAC fan has been starting and stopping fine ever since. What's wrong with your unit?

Good Luck- those new units are absurdly expensive....

Kenny
93 RSA
97 748

burgass

Mechanic says - everything?!?
These are the symptoms:
1)AC not cooling enough
2)Driver side blower works on self decided intervals
3)When you dial in 27C degres it is only 15-17C in the side
4)Defroster booster sometimes sounds as it is not working on full power.

The repair shop says they pluged in some instrument that could check for faults and they got weird things like -2C on left side and 162C on the right, engine temp 120C while the engine was on only 5 min.
Then they pluged in a 993 CCU and that one showed normal values but drained the battery. Conclusion - I need a new unit. New CCU costs 1500 €
They also say the left blower should be replaced because it works eraticly.Thats acording to them around 1000€ also. So I am not happy today....Maybe somebody can help me find a company that can check the unit.
Regards

kennyjr748

Otto's is in California- they can fix your unit for about $300 US.
Here's their link
http://www.ottosvenice.com/

Good Luck
Kenny

Randall G.

There is a place in Italy that repairs CCUs, per this tech article on John M's website:

http://www.porsche964.co.uk/technical/climate.htm

Adrian

Dear Burgass,
Not one of those symptoms would be sufficient for me to conclude the CCU has failed. The CCU has nothing to do with how cold the aircon gets unless you still have heat selected and that is not the CCUs fault.

The rest of the symptoms indicate a problem with your rear blower fan in the engine bay.

A 993 CCU will NOT work in an 89 C4 without wiring modifications.

What I recommend is that the 964 be looked at by somebody who knows what they are doing. Obviously the people you are dealing with do not know what they are doing. This is harsh but the fact they fitted a 993 CCU into a 89 C4 tells me a lot.

I recommend you open the engine lid. Take the cover off the left side fuse and relay panel and check the fuses.

The aircon issue is separate from the rest.

I also reluctantly say this but my book covers this in depth and I know will help you and guide you through such issues. It was written for this purpose.

Ciao,
Adrian
964C4

Kahdmus

Adrian, do you cover the wiring of the CCU in your book? (yeah, yeah, I know, only a few days to wait and see!) The PO of my 964 did some brutish rewiring of mine and it requires a HUGE troubleshooting effort(which is why Ive never posted for help on this one!) If I understood how the thing was wired I could perhaps begin to troubleshoot!

Cheers,

--H

burgass

Thank you Adrian and everybody else!
You would not believe me if I told you that the diagnos comes from a Porsche authorised place and there are only 2 such in my town. Good thing is that I am on good speaking terms with them so I can discuss such issies and sometimes they listen to me. Will be doing that tomorrow. I hope that I have not missundeerstood the guys but they said it was a 993 unit they plugged in. Very strange!?!
Adrian I will purchase your book as soon as it gets out. Feel a lot more sure to do my homework before accepting diagnosis from the service shops
I will inform the forum about what happens tomorrow
Regards

Randall G.

They might have meant an updated 964 controller which starts with 993. In which case, only a simple jumper is required to make the CCU fully functional on your car (not having the jumper will prevent the rear blower from running in fast-speed). Actually, the 993 & updated 964 CCUs both use the same part number, with the exception of the suffix (last number).

Adrian

Dear Randall,
Yes it is only a simple jumper lead but that is not the point. If they did not do this, if they do not know this then more problems will be created.
I also have to correct your last line. The 1994 and 1995 993s use their own control unit which happens to function almost the same as the 964. The 964 does not have the double aircon blast buttons except the very last ones. The 1996 and up 993 control units do not work in the 964. That little double digit dash number at the end can signal some fairly major changes in a product.
I will provide one engineering tip. Any change in a part number even the last two digits indicates a change in Form, Fit or Function. The impact of this change in form, fit or function is what often leads us to problems.

Dear Howard,
Yes all this is covered in depth in my book including a table of what works and what doesn't work in a 964 from the 993 series. RHD and LHD.

Ciao,
Adrian
964C4

Randall G.

>Yes it is only a simple jumper lead but that is not the point. If they did not do this, if they do not know this then more problems will be created.

Why isn't this the point? It's quite possible the dealer installed the correct CCU for his car, albeit with a 993 prefix. It's quite possible all burgess heard was the "993" part. Even if they didn't install the jumper, the updated 964 CCU (993 prefix) would work in his car, short of the rear
blower operating at reduced speed when the heat is on.

>The 1994 and 1995 993s use their own control unit which happens to function almost the same as the 964.

Are you you sure about this, Adrian? According to PET, there is a CCU to fit 911s through '94, and another one to fit 95+ 993s. I don't see a CCU that only fits 94/95 993s. Which is consistent with what I was told by the parts manager for Sunset Porsche. They only sell two CCUs--the 95(+) 993 unit, and the updated 964 unit. (Of course, over on your side of the pond, your OPC will sell more than 2 CCUs, considering cars w/o AC, LHD, RHD).

According to the PET part numbers, a '94 993 CCU should work in a 964 = same part # as the updated 964 part #. Unless you live in the US, where a '94 993 is not to be found.

Arjan B.

Adrian, what do I read....... THE 964 DON'T HAVE THE DOUBLE AIRCON BUTTONS????

This is not completely correct Adrian. I have a March '92 964 With double aircon buttons. Car came frome Italy, may be this is why I have those.

I hope you wll give the answer why I have the double buttons though.

Nice weekend!

Adrian

Dear Arjan and Randall,
Okay I am done with this stuff.
For everyone else there is table in my new book on this subject along with photos of the actual control unit testing that was done to find out what works and what does not work. This testing was done in Switzerland, England and Hong Kong.
I am sorry but I have no time to run around in circles. I have a deadline to meet with my new book and I have no time to argue or answer questions like Arjan has posed which he can easily answer for himself.
Ciao,
Adrian
964C4

Arjan B.

Adrain,
This was just a ordinairy question from my side. You said the late 964 have those, that will be the 1993 and 1994 964's. In my case it's a early 1992 car. Why do I know the answer on my question by my self???? I gave a suggestion that the car came from Italy, this does'nt mean that I know the answer, I 'think' that this could be a possible reason to install a double button unit.

Why do you always quit posting after somebody starts to discuss with you. You are well informed about eveything about the 964's, so that means that you will have some difficult discussions now and then with people. Don't quit every time, we can discuss nicely aswell. I know that I am in the top 10 of the most 'stubburn' guys on Rennlist, but I am stubburn most of the time because I come with facts, and yes' I make also faults now and then, but when I do, I correct my self and appoligize then.

Great day Adrian!

Adrian

Dear Arjan,
I do not have the time. If you do not accept what I say then fine but I am done arguing and discussing such things. Check your owners manual. Do you see two aircon buttons on the control unit. I have a 1994 manual and it does not show it either. I know that 1994 model years got them when they ran out of 964 units. Your C2 was NOT delivered with a 993 control unit. If you have a 993 control unit now then it has been changed. I should not have to tell you these things.
Ciao,
Adrian
964C4

PS: PET is a good guide but in many areas inaccurate to say the least. It says thing may be fitted but it does not say if they work. This is why there is a factory manual to be consulted and technical service bulletins to be consulted. Plus many other docs.