Thanks for posting your question. The problem is caused due to two reasons, one if the cartridge is defective or two if the printhead is defective. The lights only lit up when the printer is not able to detect the cartridge and this can also caused due to defective printhead, because the printhead work as the medium between the cartridge and the printer and if the printhead is defective the printer is unable to detect the cartridge. Now the solution for this problem is replacing the printhead, but before that open the link below and follow the steps to remove the printhead from the printer, after that clean the gold contacts on the printhead with a cotton swab and distilled water, after that check the result. If the problem persists then, unfortunately the printhead is defective and you have to replace the printhead to solve the problem.