Which ecm, ecu, pcm or whatever you want to call it electronically controls the mg1 or mg2 aka the ice starter? A pic would also help.
It’s MG1 that starts the engine. The power management control ECU (HV CPU) does comprehensive control of the hybrid system; a separate MG ECU, part of the inverter with converter assembly, directly controls MG1 and MG2, according to instructions from the power management control ECU. Depending on why you’re asking, the links in my November 2019 posting might also be of interest. See 2010 Prius New Car Features (more info), under Engine/Hybrid System: Hybrid/Battery Control: Hybrid Control System: System Diagram.
