2011 CITROEN DISPATCH NON START

[spannerman0785]

My 2011 citroen dispatch 2.0ltr hdi cut out the other day and wont restart. Had a diagnostic guy out who told me that it was a faulty ecu. Since had it to another garage who scanned it and came up with fault code P0337 engine speed signal short circuit between 2 wires or open circuit. They have since managed to erase this code and thevehicle tries to start, fires but then gives up. Im assuming that the scanner recognises the ecu but if you try to go back into it after erasing the codes it comes up with no communication. Any help would be appreciated.