The original fault of the remote not working could be a few things, first off, most of the newer sets don't use just a photodiode anymore, they use a 3 legged module that is screened from daylight and rf, so maybe if you're luck it's just dry solder joints...if not, the three connections are usually Vcc Gnd and data...so a quick scope check will show you if there is any data being put out, if you haven't got a scope, a logic probe will do to listen to the data stream...