Missing part from immobiliser system

after installing a 2012 dash loom in my 2008 Tacoma (hilux here in oz) I have a code coming up P2799. Looking through the manual and checking out the loom it seems that I am missing an important part. Not sure if this is the cause (the key has been coded correctly and the security light goes out) but still won't start.

https://youtu.be/-iSwDAEf2K4

Anyone know what the part number I need or can properly identify it?

 

This is an engine immobilizer code, the computer does not recognize the key you are using. Make sure you are using the key that always started it before, any other non programmed key will not work, it has to be a key with a transponder chip and it has to be programmed to work with the computer.

 

This ^

 

The security light goes out with this key so I’m assuming the transponder works fine. I’m thinking it is something to do with the security ecu or amplifier that is the problem

 

Sounds like the transponder isn't giving the ecu the signal... Well good luck!

 

Update. I checked the injectors and the spark and they both work temporarily. This is leading me to believe the ecm/security is shutting it down.

I also realised that if I turn the key completely off and then back on that is when she runs briefly. If I just turn it from accessories it won’t fire at all.