If it is the pats system at fault or the keys are not programmed then the engine will not crank.

Seeing as the engine is cranking this suggests that the fault is elsewhere.

Check to see whether you have live feeds at the coils or injectors (12v) and check to see if you have a live feed at, for instance, throttle position sensor (likely to be more like roughly 5v). If so the ecu and main power relays are ok and you are getting the power where you need it.

If that checks out ok, then check to see wether you have a switched earth on the other pin of the coil or injector plug you checked for the live feed. If no and the fuel pump does not run on cranking, this suggests a possible crankshaft position sensor issue. The ecu needs the engine speed signal to switch the earths to the injectors and coils and to switch on the fuel pump.

Hope that helps.