Well, the older ones have the starter cutout when the alarm is active - but they are very old - yes I'd expect to see the starter cut out if that happens...
Newer ones if the fuse is popped that powers the BSI/CPH, then yeah, the BSI/CPH won't send any signal to the engine controller, however as OP has said, the CL control is evidently working, because the central locking motors are running and the fob signal is causing the CL controller to run the lock motors. The fuse isn't obviously failing/unfailing - the problem here might be to do with the BSI/CPH being faulty, however fixing door looms and locking/unlocking the car will not bring this back to life, that would then be a faulty BSI/CPH - but again, it's is an entirely different system, it just so happens that the device that sends the signal to the CL controller is within the same box as the device that controls the transponder system.
Newer ones if the fuse is popped that powers the BSI/CPH, then yeah, the BSI/CPH won't send any signal to the engine controller, however as OP has said, the CL control is evidently working, because the central locking motors are running and the fob signal is causing the CL controller to run the lock motors. The fuse isn't obviously failing/unfailing - the problem here might be to do with the BSI/CPH being faulty, however fixing door looms and locking/unlocking the car will not bring this back to life, that would then be a faulty BSI/CPH - but again, it's is an entirely different system, it just so happens that the device that sends the signal to the CL controller is within the same box as the device that controls the transponder system.
