Error 19 Need Help!

Snapped the chain on my bike a few months ago, a 2003 model, chain shattered through the oil filter covering the back wheel, was hell of a sliding 180 but somehow managed to stay on although when the bike came to a halt i couldn't counter the stop and had to lie it down gently then get off to pick it up.
Obviously engine cut out and i flicked it into nuetral, everything seemed fine so turned it off and pushed it home, couldn't start it as the battery had been flat (i had jumped it that day). Bike stood for a while and consequently battery totally died, i bought a new one, fitted it and turned the bike back on, tried to start it and have engine management light on with error 19.

I can't say if this error was there the day the chain snapped but i'm sure it wasn't, Have found out that it is error code for the sidestand switch, checked all wiring thinking the chain had gone through it but all is fine, I traced the wire to up under the tank where there is a connection block, i seperated this and crossed the terminals to see if there was a problem with the switch or not - still the same error 19 and won't start.

If anyone has any ideas i'd be grateful, do i need to reset anything once the switch has been replaced or fixed? will crossing the terminals work or does the ECU know it's not the real swich? I've traced one wire back to the ECU and there is no deteriation anywhere, the other wire goes back into the loom up to the front of the bike somewhere but as yet have not traced it's destination.

I have looked at many other electrical fault threads on here and they all seem to have stemmed from the bike at some point being on it's side can this be a factor? Starting to puzzle me a bit, all i want to do is ride the damn thing!!