As Castek Resources stated
"You could easily make the situation much worse (and more expensive) if you are not very careful.
If you are able to siphon ink via captop, it's not a supply issue. If you removed or inserted the ribbon cables on the print head while the printer was plugged in, as previously mentioned you blew a fuse. Cables must be swapped in pairs and in the same order. If possible you need to locate a tech that has the ability to replace the fuses and not just swap out the main board. You may even have a shorted head if you dropped any ink into ribbon connector on the print head or a bad ribbon cable.
This forum is a great source of information, but you are at a point that you need professional help. The main board can usually be repaired with new fuses. Now that you have no signal to either head it is impossible to troubleshoot without replacing them.
Sounds like this may have been repaired by replacing a $25.00 cap top. If they are over 6 months replace them. The ink system is not pressurized. If you don't have good seal around cap tops / heads, the pump will not be able to pull ink from the cartridge, ink lines, dampers, manifolds and then into the heads resulting in drop out.