Technical Description (Comment)
WARNING: This page is about a different car, the 2014 Mitsubishi Outlander. However, it is still accessible from the selected car via links, so may be relevant.
When the vehicle power does not turn ON (not possible with power supply mode ACC only), the possible cause may be that the OSS-ECU cannot output the ACC signal, or that the ACC internal relay of ETACS-ECU does not turn ON. Therefore, OSS-ECU or ETACS-ECU may have a problem.