I recently replaced a two-year old set of P400 carts with a new set from inkjetmall. Today I refilled the carts for the first time and reset them with the P400 chip resetter. But the printer gave the ink light for the Orange cart. My understanding of the ink light is that the chip is registering low, which means the reset (or the chip itself) had failed. I tried resetting the chip several times but could not get the Orange ink light to go out. Finally, I pulled the chip from the new cart and replaced it with the chip from the old cart. I was then able to reset it successfully and the Orange ink light went off.
HOWEVER when I ran a nozzle check, I got the Epson “It’s almost time to replace ink cartridge(s)” popup showing that the Orange cart was LOW!
UPDATE: I reset the chip a second time and now the Printer Settings show the Orange cart is full. I’m happily printing again, but would still like to understand what happened here.