If i riged a bulb up as a test lamp would this idea work to check earths from ecu?
I just use multimeter set on resistance or many now have buzzer circuit tester. This won't test if you have a short from one wire to another if you have burnt wire insulation or crushed wiring but you seem to have no connection at all to earth
If no joy would it be possable to have ecu checked out any where?
Plenty of places around. ECUdoctor etc