Tore and Loren,
Regarding a replacement ccu of new design. If it was a manual versus auto temp, easier to make a replacement? Kind of like a digital version of the manual system found in a earlier 1970-1988 911?

 

"If it was a manual versus auto temp, easier to make a replacement?"

Of little significance, the present CCU temp control operates as a servo control system keeping
the temp at the operator's setting. It's just doesn't have buttons to set the temp nor a digital
display to indicate the actual temp.

 

Sorry, I should have been clearer. Th original unit had a non-operational max-air button and when he took it to the Porsche dealership to have it fixed they told him it wasn't possible and got him to replace the whole unit for $1500!

 

gmorat, you seem to have a fault in either the two SMT transistors or the resistors next to them. I do not know yet what purpose they have in the CCU.
Below is a pic of a CCU front PCB in working condition.
Cheers,
Tore

 

"you seem to have a fault in either the two SMT transistors or the resistors next to them"

It can also be a circuit track that 'runs' near those devices that 'carried' too
much current.

 

So.......

I sent the CCU off to get fixed and 2 of the circuit boards have to replaced. The main PCB and the small unit that sits on the back of the faceplate. Anyway, they are being swapped out and the unit should be back in my possession next week some time. I have been told by the place fixing it NOT to plug it in until the source of the problem has been diagnosed and repaired. The wiring from the CCU to the blower and the blower itself need to be tested for shorts.

I'm arranging for somebody to look into all of this as soon as possible.

Who can say what the issue ends up being.

Good times! At least the weather is nice so having air whether its hot or cold isn't a major issue at the moment.

G

 

Is there something wrong with your ECU relay? My understanding was that it took the high current load off of the ECU. Fix, replace, whatever you do I would find out what load fried the thing before plugging in a replacement.

 

So the CCU takes its high current load offa the ECU? I'll check the relay as soon as I can. Any and all suggestions are welcome.

G

 

When you get the CCU back, ask for the 2 failed circuit boards and take a close up photo of the components that fried. I can do some reverse forensics and figure out the possibilities.

 

I already asked them to make sure they shipped back the failed components so this will be no problem.

Awe.
Some.

G

 

Which relay is the ECU relay? I looked in the fuse box and couldn't identify it. Maybe I'm being thick.

G

 

Did you check chart on the underside of the lid?

 

I didn't see any relay marked ECU. Is it possible that it would be marked something else?

 

I do not understand what pp000830 means by "ECU relay". There is no such thing.
The closest I get to his statement is the fact that the Climate Control Unit is controlling the front fan speed, and the high fan motor current is taken care by a "Final Stage" amplifier placed just behind the fuse box. (under the plastic covering) This module can fail, and could kill the CCU. However, I find this rather unlikely in this case.

The CCU is also controlling several relays, i'e. the oil cooler fan speed relay, condenser fan relay and so on. I also find it unlikely that one of these have killed the CCU in this case, but it is difficult to tell without having seen the CCU PCB's and any failed components. (or statement from the repair service)
Cheers,
Tore

 

It looks a bit of a mess, glad that it has been contained to the cct board and ribbon tape.

I would suggest that you have had an insulation failure of the ribbon tape on the outside of its bend, when the cct board is in its normal position.

Does the tape rub against or may have rubbed against anything when it is in its original position?

Not a nice smell, you will never forget it