(SOLVED) Corsa D no comms with BCM

HI I have a vauxhall Corsa d 2009 I am unable to connect to BCM PAS ABS ECM. No start situation. Showing F In dash display ( Vehicle was ok before it was not used for two days )
I have bypasssed PAS and ABS on can lines still no connection. I have checked can lines from diagnostic connector to BCM through all units to ECM all have good continuity. Dash lights as usually only fuel gauge showing empty. Tried swapping out BCM (only difference is spanner light flashing )with a reset unit still the same dash and ECM swapped still the same. All lights central locking ect working. Can connect to radio and display, air bag module and dash ok. Dash gives code for incorrect data from BCM 
Anyone have any ideas please?

reprogram/pair the bcm with car
common fault if battery drained
bcm looses all info

How do I reprogram BCM if I can't communicate with it via diagnostic port, would it have to be via a vauxhall dealer ?

m8, it looks like you have power issue, have you checked your maxi fuses?

Yes maxi fuses ok and all other fuses checked can't understand no comms with BCM as all systems seem to operate and it has power,  power to ECM also !

Then you may have fault module somewhere which can lead to can bus network issue.
Test can bus with oscilloscope and upload photo of the signal pattern.
Also pull out wiring diagram and check can bus wires from the obd port to the first module.
If for example can wires go to ABS module first and then to the rest of the modules, you may have communication with ABS, but not with other modules if there is wiring issue after the ABS.

Thanks for all your help now solved units may have live and earths, but the (ignition main circuits relay 1)  in engine main fuse box was the problem, stops can communiction between modules think it powers the BCM seperatly from the main power feed in !!

Thanks for all your help now solved units may have live and earths, but the (ignition main circuits relay 1)  in engine main fuse box was the problem, stops can communiction between modules think it powers the BCM seperatly from the main power feed in !!

Hey mate can you take picture of defect relay

I have a corsa d here that has exactly the same symptoms and things,but relays in fuse box are ok tested,fusebox opened,tried already abs/eps/engine ecu/fusebox/ checked wires.what the hell is this faultttttttttttttt