Technician Handbook 601 Hybrid Systems for Collision Repair Compound Gear Unit The Compound Gear Unit (CGU) mechanically joins the engine, MG1 and MG2. The compound gear unit contains two main parts: • A power split planetary gear, which splits the power from the engine between MG1 and the wheels • A motor speed reduction unit, which lowers MG2’s rotational speed so it can be used at the wheels The compound gear unit also includes a counter-driven gear, final drive/driven gears that connect the assembly to the differential, and a parking lock gear. 13 Collision Repair & Refinish Training