How to reset u2-40 for sharp AR266 photocopier

Since this appears to be a non-US model I can only base my response on the closest US body type AR-M237.

U2-40 means the countdown (CRUM) chip in your toner cartridge either broke or went to zero. If you can put in a fresh CRUM chip in your cartridge, that's great, otherwise you'll have to replace the toner cartridge.

L4-01 means main motor lock, probably due to a brownout or otherwise missed timing. You can probably get by with a power off and on. Not sharing your copier with other devices on the same outlet will also help here.

To reset error codes, put the machine in test mode with the four-key combo: # - * - C - * ... 16-Start clears your U2 trouble, 14-Start and 17-Start clear the rest. Then hit CA and allow your copier to reboot. Good luck!