Hello everyone, as the title suggests, I am in need of help with bypassing the immobilizer on a K Series 1.8vvc Body Control Unit, I have the matching ecu and key fob.
The Issue lies with the wiring loom within the car, and from what i can tell, the loom connecting the ECU to the BCU. My 1.4 shell has a mems3 pectron unit, however the 1.8vvc BCU doesnt appear to be mems3/pectron because there is a difference in multiplug amounts/layout. because of this i cannot start the car. Im hoping that i can easily/quickly bypass the immobilizer rather than strip down the dash to replace the interior loom.

Sorry for the long post and thanks for any and all help

the immobilizer or 5AS unit if that is what you mean can't be circumvented.
ECU, 5AS and key fob are matched. Only way around it is to have the MEMS ecu engineered by a specialist for it to work without the 5AS.
I have some pintouts for the 5as that might help you rewire the plug(s) if need be.

In order to do this you would need the pinout for the 5AS that use to come with the car and the pinout for the one you're putting in.