Question about Brother MFC 7840W Printer

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Want copier to use up more toner in machine

The copier stops when the MACHINE detects the toner is low. How can I cover up the "Toner eye", so that it will keep printing and use up the toner in the machine until I say it is low?

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  • ourzoo1 Jun 23, 2009

    I read in a review of this product that one person resolved the problem by covering the toner eye. Does anyone know where the toner eye is in this product?



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If you know where the "Toner Eye" is in the copier, cover it with black tape. Usually though, the copier counts the number of pages printed and then at a predetermined number thinks toner is low and stops printing. If the toner cartridge is chipped (has a electronic chip) it keeps the count in there. These type of cartridges are refillable, but still have the "Empty" count. The counter must be reset. These resetters are hard or impossible to get.

Posted on Jun 23, 2009

  • John Moore Jun 24, 2009

    The toner eye would have to see into the cartridge. The trouble is: the toner covers everything. It would cover the inside of the window and always look full. The easier way is to count printed sheets. Once the count reaches a predetermined number where you still get good printout but before the toner runs out, quit printing with that cartridge. Use a memory chip on the cartridge to keep the number so the cartridge could not be removed, refilled and re-installed and print more. The counter still says out of toner count and will not print.



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