[Richard_G]

There is no motor behind the instrument panel, as mentioned there is the aspirator for the HEVAC in the centre of the dash and there are the blend motors that are a little closer, You need to delve into the ETM a little deeper and check where these additional wires are attached, Only ever seen a Webasto pre-heater on a diesel, not a petrol.

 

[Richard_G]

Does it stay running? There's an ignition switched supply that remains live for 30 seconds after you switch the ignition off. Amongst other things it is the positive supply to the fuel injectors but is often used as a supply for aftermarket add-ons (my LPG ECU is powered off it). A pair of Black/Green wires going to the BeCM doesn't help a lot, there's 17 multiway connectors going into the BeCM and I suspect quite a few will have a Black/Green wire.