Hi James


Are you checking the crank signal at the ecu?

Voltage drop testing should be used to varify relays and connected circuits.

'If I give supply from main by bridging why is voltage present but not when relay in position?
Wiring must be intact.
I swapped main relay to remove from equation.
Am i missing something here?'

Im not sure exactly what you are saying here (Im tired)
If I have read it correctly I would be checking the control side of the relay



hth
James