Some vehicles are wired backwards, with a halogen bulb it doesn’t matter what way the power is connected, (-to+) or (+to-) because it is a filament. An HID kit is polarity sensitive, so it can only be connected one way. Simply flip the plug (a) that powers the ballast the other way and it will work. Don’t worry about hooking it up backwards because the ballast has a safety feature to protect itself.

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