The circuit that is normally cut to cancel the ABS is the circuit of the ABS electric motor (30 amp fuse)...but "normally" the logic of the vehicle computers is more or less like this: the hot wire that arrives to the electric motor, it returns to the ECU through the negative and that way the ECU knows that the fuse is good and that the motor is not blown (the positive does not go to ground and blows the fuse)...now, when The ECU wants the engine to work, that negative cable through which the positive signal returned... simply with an internal relay in the ECU it sends that negative to ground and there the engine now has negative to rotate. …if you look at the ABS components, you will find fuses (for the abs motor and the abs ecu), but you will not find abs “relays”…which is strange for a hot circuit. Everything that consumes current on the motorcycle has its hot wires through a relay (horn, stop light, starter, fan, headlights, etc.)…except the ABS motor (with a 30amp fuse??)…. It does not use a relay, that is, the electric motor is always hot, but the negative wire is not a wire, it’s inside of abs ecu
When you cut the 30 amp circuit, a fault is informed…
It's like a burnt out lamp sensor. 12V enters through the positive, and returns to the ECU through the negative cable (for example 10V because of the filament), with this the ECU knows that the filament is fine...if nothing is returned, the filament is cut..(fault code)….and When the ECU wants to turn on the lamp, it sends that return cable to ground with an internal relay….