Burnt SATA power connector/cable

An interesting issue that I had to look at today – a burnt out SATA power connector. Some pictures:

Burnt SATA power connector

The connector on the control board

Burnt SATA Power connector - drive

Another view of the connector on the control board - note the scorching of the surrounding circuit board, but the lack of any burnt out components or tracks

Burnt SATA Power Connector

The SATA power plug. I think I see the problem here...

Burnt SATA power connector - molex plug of adapter cable

The Molex connector which fed the SATA power adapter cable. Note the damage to the insulation on the 5V line

Burnt SATA power connector - molex plug and wire of adapter cable

The Molex connector of the SATA power cable adapter. Note the break in the 5V wire where it was vapourised.

My guess is that the SATA connector, where it plugs into the drive, had some sort of short between the pins on the drive’s socket. It must have pulled a lot of current to so completely melt the connector, and vapourise the 5V (supply rated for 30A) copper conductor. There was no obvious damage to the circuit board or drive, ruling out a failure on the board/drive causing a short.