Serivce error, VT will not start after engine swap

[ka1sa226]

So I just finished replacing an ecotec in my vt and when I got to try it out the "SERVICE ERROR" message pops up in the dash window and the car does not crank at all. So far I have tried resetting the computer, undoing the bcm, checking the fuses. When I did the engine swap I used the wireing loom that the engine came with. I don't have ABS and the security light is flashing. I've been told that it could be a dodgy ground or a ground that isn't connected properly, if anyone can tell me where they all are that would be helpful.

[accentstencil]

Are you using the same ECU and BCM that you had before?

[ka1sa226]

Using the original ecu and bcm. But I swapped the ecu for the one that came with the engine and that didn't help

[1SIKR8]

are all the sensors hooked up ? i'd double check that

[ka1sa226]

Checked over the engine lots of times. If there's any I'm particular I should check please say. Also can't seem to get any error codes. Not even the default 12

[1SIKR8]

crank angle sensor, thats one that will stop a motor from cranking ... if i think of anything else i'll get back to ya

[ka1sa226]

Also if I go into the menu wher it has digital speedo fuel in tank etc it said my temperature was -40c so I checked it and it was unplugged. Pluged it back in but didn't seem to affect it. Also tried starting car without ecu and nothing changes whether it's plugged in or not

[delcowizzid]

did you plug in the under dash wiring plug to the ecu loom lots of people dont

[ka1sa226]

Do you mean the three fat plugs Leading to the ecu?

[delcowizzid]

theres 3 plugs that go into the ecu then further up from the ecu is a plug to plug the ecu loom into the dash loom .it has all the ecu ignition switched power feed for ecu and shit in it for dash and for pcm-bcm connection

[ka1sa226]

Sorry not really sure where to look could you be more specific?

[ka1sa226]

Please I need this fixed asap