Standalone ECU wiring with Battery Isolator

Heya everybody.

Picked up a new project and it escalated a bit, to the point where the car is going full standalone and a custom harness.

It's my first ground up project and one of the questions i have is related to correctly wiring the Cartek isolator to the Emtron KV8.

The Cartek XR calls out the "Engine kill signal", to either send the shut down signal to the ECU, PDM or potentially control the engine relay.

For the KV8, it recommends that the ECU itself controls the EFI/Engine relay, which in turn disconnects power to the ECU 12V supply and/or other components.

I'm currently thinking, the isolator is the main power on/off for the car, which when turned on, will turn on the dash, keypad, PDM and ECU, with then a separate "ignition switch" for coils and so forth.

For a setup like this, would the Cartek kill signal be tied to the "ignition switch" side of the KV8?

In addition to that, could the KV8s EFI Relay Output Pin be tied into the PDM as a signal, which turns off supply to the Injectors/Coils?

Or am i overthinking this, and the "Kill signal" from the Cartek is to be used as an input into the PDM which then turns off the ECU via it's ignition switch?

Guess there are a few ways to get this done, just not sure what the preferred method is in this case.

Thank you!

Since you say you have a PDM and keypad. I would bring the Cartek kill signal into the PDM on one of it's inputs. Then the PDM can generate an Ignition switched power combining the Cartek kill signal, and the Keypad Ignition switch function. That output is what controls the power to the coils and the ignition switch input to the KV8.

I would tied the KV8's efi relay, to the PDM. That probably get's used for things like after-run fans, pumps, etc.