I've added the 4 diodes and removed the resistors. I've removed the switch too (cos i didn't want it but dont think that will make a difference). But when I connected the 12c battery, another sn754410 chip burnt out 
I've added the 4 diodes and removed the resistors. I've removed the switch too (cos i didn't want it but dont think that will make a difference). But when I connected the 12c battery, another sn754410 chip burnt out