# Specific 3D Printers, Scanners, & Hardware > Other 3D Printers / Scanners / Hardware >  Creality Ender 3 main board upgrade smoke

## spetz

Hello all,I'm doing a main board upgrade on my Ender 3 to V4.2.7.I've double checked the wiring and when plugged i get a spark and smoke coming from F2 (fuse???)Any ideas on how to troubleshoot this?Is there a detailed schematic?Printer was functioning fine with the V1.1.4 board.thanks

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