I don't belive both LEDs are dead by burning-trough since they are protected by 220 Ohm resistors.
A500 LEDs are in fact 2 double LEDs soldered at small PCB which is integral part of A500 keyboard module. Their operation is triggered by signals from motherboard. Each LED pair has its own wire coming from motherboard to keyboard module.
To check connectivity of those wires, open Amiga plastic casing by removing 6 torx screws from bottom side. Then remove keyboard plate slightly forward just enough to put it aside. Now check those 2 LED pairs for loose solder contacts from backside of PCB plate. If they are firm, move on.
Keep your focus on 8-lead flat cable connecting small PCB at keyboard module and motherboard connection acessible trough opening in RF metal shielding. That (MOLEX) socket sould be firmly attached to the A500 motherboard. According to schematics, your signal lines should be first 2 wires from the right, when looked from topside. Usually, it is one violet and one blue wire.
If socket is firmly connected, then proceed to voltage check. Get a multimeter and check voltage at each signal wire, you should expect 5V when power LED goes ON, or FLOPPY drive accesses media.
This should eliminate all SERVICEABLE troubleshooting, except de-soldering LEDs and getting spare ones re-soldered back to PCB.
