Hi there, thanks for your message. There could be a number of reasons for the red light. I assume the first printer you mentioned is a Brother HL1212W and here is a link to the Brother website that explains the different reasons for the red light.
Brother flashing light reasons. It looks like these do seem to be related to the toner and/or drum unit. Has the new toner cartridge been inserted into the previous drum unit correctly before it was installed into the printer? This could be the reason for the issue. Hopefully, the link will help explain what the problem might be and help you to get the printer working again without needing to buy another toner.
For your HP printer, it could be an issue with the power cord not working anymore, so before you replace the printer it would be worth trying to replace the power cord and seeing if that fixes the issue. Power cords tend to be very similar between different printers so you may be able to test by using the one from your Brother printer but make sure the amps and volt value match to the HP printer so as not to cause any damage. Other than that, it would likely need a technician to take a look at it or to replace the printer, unfortunately. If you need any more help, please let us know!
