Whilst testing out fan headers, I accidentally shorted 12v to ground and the printer died instantly. I tested the power supply and got 12v there and at the terminal block too. I grabbed my multimeter and quickly found the suspect 5A SMD fuse, near the power terminal block.

Except, I had no replacements.

Its hacky time.

Strictly speaking – replacing a fuse with one of the incorrect rating is a big no-no and places your system at risk. At the point I found myself at, with a big print job on the decks and and an out-of-commission machine, I decided to take a chance and risk it. I felt a bit more comfortable doing this as I knew exactly what caused it to blow. Had it blew suddenly, I’d have been more apprehensive because I’d not have known the cause without some prior investigations.

The fuse I had on hand was rated the same but slightly different in that the replacement ceramic (polyamide) fuse was the ‘slow blow’ variety and while it offered some protection – the risk of damaging more sensitive components was a real one if the surge wasnt big enough to blow it straight away.

The risk accepted, I battled to get the SMD fuse off and was worried about destroying the traces so I just soldered it over the original fuse as a temporary solution. I gingerly powered it up again and much to my relief the board powered up and it kept chugging along.

Disclaimer:

DO NOT try this at home. I like to think I know what I’m doing and was willing to risk damaging my equipment.