Sounds like a problem with the connector. I've had issues like that before where a faulty connector caused the connector itself and the wiring to get real hot.
2000 Mustang GT Steeda #0048 34k miles. 99 Cobra 4V swapped, FTBR IRS swapped, exhaust, tuned by James Gordon.
Just because I give you advice, doesn't mean I know more than you. Its just means I've done more stupid ****.