I would say that it is neither a witch nor a chupacabra, that it's more likely possessed.

There's likely a bad contact or decaying wire inside that harness and I would carefully dismantle until I found the culprit and fixed it.

If ghosts start to come out while you're dissecting I would walk away from it...lol

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Steve A
92 W140 OM603
97 VW Jetta TDI
90 Passat variant TDI 6 speed MT
94 Chevy K1500 6.5TD
05 E320 CDI
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