MBE 4000-CURRENT IS NOT GOING TO N0 1,2 AND 3. INJECTOR CYLINDER

Dear all, I am working on freghthliner truck power by mercedes-benz, 2008 model,business class M2, LA 460 engine for the past 5days troubleshooting low current to injector cylinder 1,2 and 3.while current is fully supply to 4,5 and 6 injector cylinder, As a result of this cylinder 1,2 and 3 has stop functioning while cylinder 4,5 and 6 is functioning correctly. So truck idle is not smooth and rough sound when engine is rated, The following troubleshooting has been carry out such as swabbing of pumps and nozzles 1,2&3 to cylinder 4,5&6 and it work perfect while 4,5&6 pumps and nozzles that is functioning fine in his surface swabbing to cylinder 1,2&3 and it did not work because is not receiving enough current, Fine below part that was replace,Pump wire harness, Electronic control unit(Ecm), Cam and crank sensor,Vehicle control unit(VCU), Throttle sensor, Fuel temperature and pressure sensor yet the voltage is still low to the injector 1,2&3 and the problems did not stop, i need everybody advise and support to solve the issue and below is fault code i got after scanning(ecu 128 sid 001 fail 05-current below normal or open circuit) ( ecu 128 sid 002 fail 05-current below normal or open circuit) ( ecu 128 sid 003 fail 05-current below normal or open circuit) thank you all.