Help
 

Hoping someone can help!
My volvo c30 1.6d lost power a few times driving home. Once I got home I turned the car off and it wouldn't turn over after that! Diagnostic brings up 'Camshaft sensor signal faulty' so I've replaced it but still no luck. Garage said ecu isn't responding to the camshaft, back up ECU isn't responding to it either?
Car starts when 'bypassed' whatever that means. What do I do?

The ECU doesn't know if the cam sensor is good or bad, it just know the signal isn't correct. Long way of saying you may have a wiring issue/electrical issue and not simply a bad sensor. Some cars can start with the cam sensor unplugged so I sense that's what was "bypassed". Did you get the actual fault code(s) behind the diagnostic message? that may give you a better clue as to what the ECU is seeing.