Inspection Procedure 4: TC-SST-Ecu Power Supply Circuit Malfunction: Notes
WARNING: This page is about a different car, the 2008 Mitsubishi Lancer. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Power Supply System Circuit Diagram
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
CAUTION:
Whenever the ECU is replaced, ensure that the CAN bus lines are normal.