L67 VY CALAIS WONT START PLS HELP

[03HBDVYCALAIS]

Hey everyone
So I have my 2003 VY Calais with factory L67 and recently had the bottom end let go. I decided to buy a new motor instead of fixing mine as it was easier and I got a really good deal.
My old motor was stock and the new one fairly modified as far as Mace roller rockers, ls1 valves and springs, CNC machined head, smaller pulley and a few other things. Also came with a shift kitted trans.
Because of this I also got the ECU that was tuned to this motor to make things easier when it comes to tuning.
Now I have done the swap, everything is plugged in how it should be but... nothing.
I turn the key, accessories and everything come on, it does it's Holden check and it comes up as clear and I turn the car to start it and have absolutely nothing. Doesn't even try to turn over. Can't hear the starter motor click or anything either. So my thought is wiring issue.
Is it possible that the ECU could be paired specifically to the BCM and PCM from the other car and I should take that ECU out and use my factory ECU and just have to get a full custom tune done?

Only reason I haven't gone down the Memcal route is because I don't have the time to wait for it to be supplied as I need the car back on the road before Wednesday 26/08/2020 next week and is due to go to the tuner's on Tuesday 25/08/2020.

Any ideas would be massively appreciated as I am new to L67s and don't have enough knowledge to try and diagnose a problem that I have no idea about.

Thanks in advance

 

[TheIceman]

didnt swap bcm did you?

 

[03HBDVYCALAIS]

didnt swap bcm did you?

No I didn't

 

[Utel67]

Put your pcm back in and see if it starts.

 

[03HBDVYCALAIS]

Put your pcm back in and see if it starts.

I never took my pcm out, only the ECU but I'll try putting my ECU back in.

 

[Lex]

I never took my pcm out, only the ECU but I'll try putting my ECU back in.

Your confusing me?
What did you change?
Did you only change the memcal, which is in the pcm?

 

[Utel67]

Your confusing me?
What did you change?
Did you only change the memcal, which is in the pcm?

I think he's calling the PCM a ECU

 

[Lex]

I think he's calling the PCM a ECU

He is saying he changed the ecu, but didn't change the pcm.

I'm wondering what he thinks the ecu is?

 

[TheIceman]

if you swapped one not the other then it wont start until they are linked with tech2 or similar

 

[Fu Manchu]

The key, Body Control Module, Powertrain Interface Module and Engine Control Unit/Module need to have matching Vehicle Identification Numbers in their programs.

If one of those does not match, the car will do it’s job and prevent the car starting.

The above post tells you how to get them matching and with what tool.