Just a post with a fixed problem for information. I had a non starting 2007 Skoda Octavia Estate Scout 2.0TDI PD.
No engine management light, no coil light, no DPF light illuminating, all other lights illuminating such as abs, airbag etc when they should, engine just cranking over. I plugged it in through OBD using snap on solus pro. No communication with ECM under engine management. I checked other modules such as abs, airbag, they all stated no comms with ecm.
There is a relay in fuse box under bonnet with 370 on it, only relay under there. This was clicking as it should. I pulled it out and put a wire across where the switched side of relay would be and problem solved so swapped relay and now fixed. I also checked the energising side of where relay would be (12v). So be warned a relay can still appear ok by clicking but not necessarily be ok.
Hope this helps if anyone else has the same problem.