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. Seems to control the nucleotide-dependent binding of mitochondrial HSP70 to substrate proteins. Probable component of the PAM complex at least composed of a mitochondrial HSP70 protein, GRPEL1 or GRPEL2, TIMM44, TIMM16/PAM16 and TIMM14/DNAJC19. Binds to HSP70, HSC70 and HSJ1B (By similarity). Ubiquitous. Particularly abundant in heart, kidney and liver. Belongs to the GrpE family.