Climate Control Head
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Joined: Jul 2001
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From: New York
Dwayne has a great write-up on the HVAC vacuum system trouble shoot and one on the control head relay upgrade. http://www.dwaynesgarage.norcal928.o...0Procedure.htm
Chronic Tool Dropper
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From: Bend, Oregon
928 International has rebuilt heads that are done by GB if memory serves me. This rebuild includes an inline fuse in the clutch circuit to protect the relay and the board traces in the control head. Often, the board traces fail when there is a wiring fault between the control head and the compressor clutch coil. That would include wiring to and through the CE panel, the freeze switch, the pressure safety switch, the 14-pin connector, the front-of-engine harness, and the connector and pigtail to the clutch coil. For those of you with cars less than 10 years old, this probably isn't an issue.
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928 International has rebuilt heads that are done by GB if memory serves me. This rebuild includes an inline fuse in the clutch circuit to protect the relay and the board traces in the control head. Often, the board traces fail when there is a wiring fault between the control head and the compressor clutch coil. That would include wiring to and through the CE panel, the freeze switch, the pressure safety switch, the 14-pin connector, the front-of-engine harness, and the connector and pigtail to the clutch coil. For those of you with cars less than 10 years old, this probably isn't an issue.
What cars of ours are less than 10 years old?
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Joined: Feb 2005
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From: Anaheim
928 International and 928's R US, exclusively, stock my rebuilt control units. I do sell them directly to my own customers that come into my shop and need control units. However. I do not sell directly to non-regular customers.....you have to get them from one of those two suppliers.
I got tired of looking at control units that had already been rebuilt/in for rebuild that had melted traces on the board. Any kind of excessive current draw will "kill" the printed circuit board, especially when a higher amperage relay is installed. Thus the "added" fuse.
I just got a control unit back (it had only been gone for a week), where whoever received the rebuild was in too big a hurry to install the enclosed fuse. Turns out the car did have a short in the wiring out to the compressor....and that "smoked" the freshly rebuilt control head because they didn't install the fuse. That sucks, but the installer stepped up and admitted what he had done.
I have build "test" boards that test all the functions of each type of control unit, so that I know they work perfectly when they leave my hands. That was one of the problems with another rebuilder that 928 International had used, in the past. A huge percentage of the units did not "work" properly, when the customer received them. All my rebuilds get tested in a "real life" circuit, before they leave, for a minimum of 30 minutes.
A word of advice.....even if you have a control head that is working perfectly....call Roger or 928 International and get the "additional fuse" to protect this circuit. I think they both offer this "extra" fuse assembly. Money well spent!
I got tired of looking at control units that had already been rebuilt/in for rebuild that had melted traces on the board. Any kind of excessive current draw will "kill" the printed circuit board, especially when a higher amperage relay is installed. Thus the "added" fuse.
I just got a control unit back (it had only been gone for a week), where whoever received the rebuild was in too big a hurry to install the enclosed fuse. Turns out the car did have a short in the wiring out to the compressor....and that "smoked" the freshly rebuilt control head because they didn't install the fuse. That sucks, but the installer stepped up and admitted what he had done.
I have build "test" boards that test all the functions of each type of control unit, so that I know they work perfectly when they leave my hands. That was one of the problems with another rebuilder that 928 International had used, in the past. A huge percentage of the units did not "work" properly, when the customer received them. All my rebuilds get tested in a "real life" circuit, before they leave, for a minimum of 30 minutes.
A word of advice.....even if you have a control head that is working perfectly....call Roger or 928 International and get the "additional fuse" to protect this circuit. I think they both offer this "extra" fuse assembly. Money well spent!
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Joined: Jan 2003
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From: Double Oak, TX
Greg's units are like brand new as if they came in a box from Porsche.
Realy nice workmanship - but we all knew that already 8>)
Realy nice workmanship - but we all knew that already 8>)
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."