LaserJet II: Where is the fuse?
(From: Tony Duell (ard@p850ug1.demon.co.uk).) There are 3 fuses/breakers to my knowledge: The mains circuit breaker is in the AC block (right hand side of the fuser). It’s hidden by the fan duct, but that’s quite easy to remove if you have the casing off. The breaker is a little rectangular object with a button on top, on the lower PCB. Press down the button and try again. The Low Voltage PSU contains the other 2 fuses. One is in the mains side, and is a normal 20mm cartridge fuse. If you remove the casing and the bracket round the front of the printer (6 screws), you can see this fuse on the PSU PCB. This fuse is a listed spare part at ‘the Printerworks’, which is strange, since the only time it should fail is if there’s something majorly wrong with the PSU, and no other PSU spares are available. The other fuse is a thermal one, clamped to the heatsink in the top right corner of the PSU PCB (looking at it from the component side). This one protects the 24 V pass transistor that on the
