2004 C220 cdi problems

[enryte]

Hi everyone, new member here and hope that someone might have a pointer for my next move.
I’ve got electrical problems with my 2004 C220 cdi (S203). I’ve had a new crankshaft sensor, camshaft sensor, MAF and I’ve cleaned out thoroughly the EGR unit. A new fuse box and the ECU’s tested. It seems now that there’s no fuel getting to the cylinders – the injectors not firing I would guess (there’s plenty of fuel to the injectors).
The diagnostic tool has thrown up 4 faults:
1. Cam position sensor circuit malfunction
2. MAF circuit low input
3. Turbo underboost
4. Crankshaft position sensor
My question is, is there a common link to all these faults?

Any help would be hugely appreciated.

 

[merc85]

Have you cleared the codes then checked what comes back?

 

[enryte]

Yes. I cleared the faults and it returned '0' faults. I rescanned and the 'MIL' readout said, 'Fuel - not ready' and 'EGR - not ready'.
I wonder if some sort of immobilising switch has been tripped that cuts off the feed to the components originally listed as faulty and stops the injectors firing?
I've been through every fuse - they're all fine.