Alfa Romeo Repair: jtd wont start, faulty cam sensor?, camshaft sensor, crank sensor

Question
Hi Steve, hope you are having a good Christmas, I have a 1.9 JTD that is havin a holiday cos it will not start, the recovery man says the crank sensor is sending a signal to ecu but the injectors are not firing (they do have 1.7V) so he thinks the camshaft sensor is faulty, I had been having some slight pinking for the previous few weeks at low revs,  I looked at the location of cam sensor and it seems to need the timing belt off? or is there an easy way?
thanks for any help
paul

Answer
Many things can cause a no start and it takes a step by step procedure to find the problem.

However, here is what I question. The injectors should have a constant 12 volts minimum  because the ECU controls them on the ground side. Also, if the man could determine that the crank sensor was ok he should also be able to be certain about the cam sensor.  You need more information before you change the crank sensor which should not need the timing belt off to change.