Any electronics boffins?

[clayt74]

Looked like the (remains) of a fuse to me - some of the on board ones look like a diode (and in some cheap kit they use a forward biased diode)

Bet you anything the regulator (3 legged thing next to it) is short.

its definitely a TVS diode! and it is there to protect the internal circuits from external voltage spikes.
the TVS diode is rated at 600W approx 50A at 12V.
if the regulator had gone short the fuse in the EXTERNAL 12V supply would have blown (and poss the |Reg burnt out in the process)
the TVS has burnt due to too much EXTERNAL voltage applied.


check the external 12v supply is indeed still 12v.
then solder in a new 23p TVS diode and all is good!!!!
good luck