Essential component of the TIM22 complex, a complex that mediates the import and insertion of multi-pass transmembrane proteins into the mitochondrial inner membrane. The TIM22 complex forms a twin-pore translocase that uses the membrane potential as external driving force (By similarity). Component of the TIM22 complex, whose core is composed of TIM22 and TIM54, associated with the 70 kDa heterohexamer composed of TIM9 and TIM10 (or TIM8 and TIM13). Belongs to the TIM54 family.