I can't really understand what you are saying you have attached to your SC. But there are two wires goin to it. From factory it is set up one of two ways (I've never looked at a factory loom)
1 - Ignition 12V is applied to one wire (doesn't matter which one) and ground is switched to the other one via a relay.
2 - more likely constant ground is on one wire and 12V is relayed to the other.
It should be very easy to work out. There is a ZE wiring diagram on club4ag too.
well the black-red stripe goes to the B+ line in your diagnosis port (Ignition 12V), the other black-yellow stripe goes to the SC relay. that gets pulled to ground to activate the charger