Quote:
It depends on your ECU. If you have the 4 peg ECU you only need the 2 prong ballast. If you have the 5 peg ECU you need the 4 prong ballast.
Not necessarily. The 4 prong ECu superceded the 5 prong setup and it a plug-n-play replacement. However, the average DIY'er would grump that his new ECU only had 4 pins and not 5 like his original and therefore must be wrong. So there was a dummy fifth pin put in alot of them to satisfy customer demand.
I doubt you can buy a non-NOS 5 pin ECU that actually needs the four prong ballast anymore. You might find a 5 pin unit, but I'll bet, if I was a betting man, that it has four pin guts and a dummy fifth pin.
They say there are no such thing as a stupid question.
They say there is always the exception that proves the rule.
Don't be the exception.
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