Mitsubishi: Engine Computer

In large transit bus engine ECUs, insufficient design review may cause the following defects: (1) During starter actuation, if pinion gear and ring gear meshing failure occurs, current continues to flow to the motor coil side bypassing the main switch contacts. If the coil sustains thermal damage, the starter becomes inoperable and the engine cannot start. (2) DPF clogging or oxidation catalyst efficiency degradation may be incorrectly detected, causing engine output to be limited and a DPF regeneration impossible warning to display, with the engine warning light illuminating on the next engine start.