Early A/C compressor relay '79
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Early A/C compressor relay '79
Can't seem to find anything in the search function about it being replaced.
Part number 928.618.105.00 is NLA and apparently a car I'm working on does not have one. Nor do the other dozen cars around here.
Has anyone found a good replacement for this relay?
Part number 928.618.105.00 is NLA and apparently a car I'm working on does not have one. Nor do the other dozen cars around here.
Has anyone found a good replacement for this relay?
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From: So Cal
The 944 uses the same relay - #944 615 113 01. They can be found on eBay and other places. I might have a good, late 944 around, but I will have to look. It could be a good back up for you. Michael
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May I ask what makes you think they are the same? I'd like to think if they were Porsche would superced the 928 number to the 944 number.
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I can put them side by side, photograph them and post them on Sunday night. Since I do not have AC in my 944 and I have an engine-less 928, I cannot actually test them. My apologies for passing along untested info.
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The 944 part number is worth checking out.
I found one, stole it from Rogers pristine '79. please don't tell him.
Here is the picture of it with the pin outs. If we could see the 944. in the same way it would sure help for future reference.
Mark, thanks for taking the time to look for me.
I found one, stole it from Rogers pristine '79. please don't tell him.
Here is the picture of it with the pin outs. If we could see the 944. in the same way it would sure help for future reference.
Mark, thanks for taking the time to look for me.
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Thats an understatement.... totally different functions
I don't quite see what the exact 31b function is... the 31b is a speed signal - the same one that the fuel pump relay uses so it only stays on when the engine is rotating.
I'd assume here its used just as an AC disable until the car is running (to keep the AC clutch disabled during cranking...?) would seem more obvious to do this some other cheaper way - eg power the relay between 15 and starter solenoid signal - Porsche did this frequently on later models for disables during cranking (for other things).
Any one know for sure what the function is (eg when is the AC clutch disabled).
I'd be inclined to figure this out and rewire it to be able to use a standard 53b relay.
Alan
I don't quite see what the exact 31b function is... the 31b is a speed signal - the same one that the fuel pump relay uses so it only stays on when the engine is rotating.
I'd assume here its used just as an AC disable until the car is running (to keep the AC clutch disabled during cranking...?) would seem more obvious to do this some other cheaper way - eg power the relay between 15 and starter solenoid signal - Porsche did this frequently on later models for disables during cranking (for other things).
Any one know for sure what the function is (eg when is the AC clutch disabled).
I'd be inclined to figure this out and rewire it to be able to use a standard 53b relay.
Alan
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Looking at the diagrams, that was my guess also. I need Doc Mirror to double check me, but I am also thinking it wouldn't be too hard to do a 53 in there.
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Keep looking guys I need AC as it's so frigging hot here in Texas.
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
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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."
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From: El Cajones CA
Here's a few pics of what the inside looks like on the 928.618.105.00 relay. This relay was in the car when purchased and didn't work. Tried resoldering the joints ala cruise control box but still wouldn't function. Ended up running some short jumpers from the CP to a standard relay, worked fine until I picked up a proper used working relay when BB500 was parting out his '79.
Maybe designed to cut out the AC compressor at high rpm?
Maybe designed to cut out the AC compressor at high rpm?