Skateboard Wired Up, But Half-Bridge Driver Over-Heating

Most of the skateboard wiring has been completed (9.5hours done on it today). The front, rear, and skirting lights work fine, but sadly, the half-bridge I.C. is overheating (even while it is idle). I don’t know what the problem is yet.

A photo of the populated motherboard.

I put all of the MOSFETs on the half-bridge in a row, so that I could easily attach a heatsink to them. The heatsink was made from a piece of Aluminium ‘T-section’.