Vauxhall Vectra B - vectra not starting when warm - frogmarch

hi my mate has got a vectra sri 130 1.8 petrol and wont start when warm engine but starts when cold codes are p1120-2, p1550-1 , p0650-4 refer to owners handbook , also when car is warm and tries to start it the spanner light through car flashes , mechanic friend says this is immobiliser how do i get round this thanks