Essential component of the PAM complex, a complex required for the translocation of transit peptide-containing proteins from the inner membrane into the mitochondrial matrix in an ATP-dependent manner. Recruits mitochondrial HSP70 and its co-chaperone (mge1) to drive protein translocation into the matrix using ATP as an energy source. Heterodimer with pam18. Component of the PAM complex, at least composed of mtHsp70, mge1, tim44, pam16, pam17 and pam18. The complex interacts with the tim23 component of the PAM complex. Belongs to the Tim44 family.