Ballast resistor is toast, I think
05-26-2003, 09:20 PM
#16
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Anyone know what the failure mode for the ballast resistor is, and what can be done to prolong its life?
Is it heat? If so can it be placed in the cooler fan airflow?
Is it corrosion from road grime and rain?
There must be some way to make it last longer, unless the new part is solving the failure problem.
Chip
Is it heat? If so can it be placed in the cooler fan airflow?
Is it corrosion from road grime and rain?
There must be some way to make it last longer, unless the new part is solving the failure problem.
Chip
05-27-2003, 10:24 AM
#17
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The new part has a metal gasket underneath it. Without it, my old one looked like the innards were dissolving :
<img src="http://members.rennlist.com/greg/993ballast.jpg" alt=" - " />
<img src="http://members.rennlist.com/greg/993ballast.jpg" alt=" - " />
05-30-2003, 01:33 AM
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The replacement parts have a heat sink attached, which should help the failure from overheating problem. I don't think there is much you can do with the stock parts. By the time you remove them to try and improve their heat resistance, you might just as well replace the part.
05-30-2003, 11:39 AM
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I wonder what the date was that the 'modified' part became available? My car had the ballast resistor replaced by the first owner 4 or 5 years ago, but it is once again non-functional.
So, if I am going to replace it again, I would like to increase the likelihood of not having to do it all over again. I've gone ahead with David's relay mod for now though. And am just waiting for clogged air injection passages to give me the old CEL so I can put his "fool the DME" circuit to use too.
Chip
So, if I am going to replace it again, I would like to increase the likelihood of not having to do it all over again. I've gone ahead with David's relay mod for now though. And am just waiting for clogged air injection passages to give me the old CEL so I can put his "fool the DME" circuit to use too.
Chip
05-30-2003, 01:49 PM
#20
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Chip,
Porsche issued a TSB (1/00 1758) on 27 October 2000 regarding the updated ballast resistor. The TSB applies to all C2/C4/RS/Turbo cars model years 89(K)-97(V).
993 616 521 01 is the part number of the new resistor with "cooling plate" for both 964 & 993.
993 616 521 00 - old resistor for 993 (NLA)
964 616 521 01 - old resistor for 964 (NLA)
I'm not sure what to make of the fact that the MY '98 cars are not subject to the TSB. I don't know whether the TSB does not apply to the '98s because a) they don't have ballast resistors, or b) they came already equipped with the updated ballast resistor? (But then why wait until late 2000 to issue the TSB for the 89-97 cars?)
Unclear whether the updated resistor was available in '98, or first became available in 2000. Maybe the '98 has the updated resistor, but Porsche waited to sell off their inventory of old style resistors before issuing the TSB?
Hope this helps.
-Dave
'90 C2
Porsche issued a TSB (1/00 1758) on 27 October 2000 regarding the updated ballast resistor. The TSB applies to all C2/C4/RS/Turbo cars model years 89(K)-97(V).
993 616 521 01 is the part number of the new resistor with "cooling plate" for both 964 & 993.
993 616 521 00 - old resistor for 993 (NLA)
964 616 521 01 - old resistor for 964 (NLA)
I'm not sure what to make of the fact that the MY '98 cars are not subject to the TSB. I don't know whether the TSB does not apply to the '98s because a) they don't have ballast resistors, or b) they came already equipped with the updated ballast resistor? (But then why wait until late 2000 to issue the TSB for the 89-97 cars?)
Unclear whether the updated resistor was available in '98, or first became available in 2000. Maybe the '98 has the updated resistor, but Porsche waited to sell off their inventory of old style resistors before issuing the TSB?
Hope this helps.
-Dave
'90 C2
