fixed DME solder joint; list just saved me > $500; breakout box?
03-21-2003, 01:08 PM
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fixed DME solder joint; list just saved me > $500; breakout box?
hallo all from a newly paid up member!
had an infuriating intermittent fault, did all kinds of tuneup work to no avail over two months, then came to rennlist, found my symptoms and went straight to the problem!
turned out to be cracked solder joints in the DME of my 87 944t. run the car, tap the DME, voila! cuts out. turns over, no spark. tap again-vroom! starts up.
just removed my DME and resoldered the joints on the big transistor. the fact that the joints are at the end of large suspended pins no doubt causes all kinds of extra mechanical stress due to vibration. this was exactly where it had failed for the member who's fix i read in the list.
got a business proposition for you--in diagnosing this problem, i tested just about all the sensors in the engine from the back of the DME. it struck me that you could fabricate what are called "breakout boxes" fairly cheaply. these tap in between the DME cable and DME box, (a passthrough cable so that the car can be run) and gives you a readout of all your sensors in situ. it would make diagnosing electrical problems for the backyard mechanic a breeze. i recently built an amplifier for my lab research, and i would say you could build something that would give you access to any two pins (say with two selector ***** and a BNC output, or posts or something) for very little, say $50.
do you think people would pay for such a thing? would Porsche sue me immediately?
cheers!
andrew spence
had an infuriating intermittent fault, did all kinds of tuneup work to no avail over two months, then came to rennlist, found my symptoms and went straight to the problem!
turned out to be cracked solder joints in the DME of my 87 944t. run the car, tap the DME, voila! cuts out. turns over, no spark. tap again-vroom! starts up.
just removed my DME and resoldered the joints on the big transistor. the fact that the joints are at the end of large suspended pins no doubt causes all kinds of extra mechanical stress due to vibration. this was exactly where it had failed for the member who's fix i read in the list.
got a business proposition for you--in diagnosing this problem, i tested just about all the sensors in the engine from the back of the DME. it struck me that you could fabricate what are called "breakout boxes" fairly cheaply. these tap in between the DME cable and DME box, (a passthrough cable so that the car can be run) and gives you a readout of all your sensors in situ. it would make diagnosing electrical problems for the backyard mechanic a breeze. i recently built an amplifier for my lab research, and i would say you could build something that would give you access to any two pins (say with two selector ***** and a BNC output, or posts or something) for very little, say $50.
do you think people would pay for such a thing? would Porsche sue me immediately?
cheers!
andrew spence
03-21-2003, 01:15 PM
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Join Date: Jul 2002
Location: Connersville IN
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I have to use breakout boxes in diagnosing abs and airbag problems all the time and they simply plug into the harness and provide a easy way to acess the pins without damaging the connectors to run resistance and voltage checks. There shouldn't be a problem legally making these as all the pertinent info is available and several companies make specialty porsche tools
