That's weird, I didn't show any continuity to the heat sink after we installed the BIP373. He had it running for a short period, so I guess maybe it heated up enough to form a place in the grease that grounded it out.
The PO claimed to have his car running with low-z injectors, but when we got it the PWM circuit wasn't even installed, so I wouldn't be surprised if something is fried, to be honest.