A connector terminal position assurance for connecting to a main body of a connector, the terminal position assurance comprising: (a) a terminal position assurance, TPA, lock comprising: a TPA locking retention contact surface disposed on a surface of a terminal blocking base; a TPA locking offset surface disposed on the TPA lock and substantially parallel to the surface of the terminal blocking base; and a TPA locking insertion contact surface disposed between the TPA locking offset surface and an additional terminal blocking offset surface; and (b) a terminal blocking feature comprising: the additional terminal blocking offset surface; a TPA anti-stubbing feature; an improper terminal detection surface disposed between the additional terminal blocking offset surface and the TPA anti-stubbing feature; and a TPA cavity guide disposed adjacent to the improper terminal detection surface; characterised in that: the improper terminal detection surface is angled such that if a terminal for insertion into the connector is not fully engaged and the improper terminal detection surface contacts a surface of the terminal, the improper detection surface is flush with the surface of the terminal. (a) a terminal position assurance, TPA, lock comprising: a TPA locking retention contact surface disposed on a surface of a terminal blocking base; a TPA locking offset surface disposed on the TPA lock and substantially parallel to the surface of the terminal blocking base; and a TPA locking insertion contact surface disposed between the TPA locking offset surface and an additional terminal blocking offset surface; and a TPA locking retention contact surface disposed on a surface of a terminal blocking base; a TPA locking offset surface disposed on the TPA lock and substantially parallel to the surface of the terminal blocking base; and a TPA locking insertion contact surface disposed between the TPA locking offset surface and an additional terminal blocking offset surface; and (b) a terminal blocking feature comprising: the additional terminal blocking offset surface; a TPA anti-stubbing feature; an improper terminal detection surface disposed between the additional terminal blocking offset surface and the TPA anti-stubbing feature; and a TPA cavity guide disposed adjacent to the improper terminal detection surface; characterised in that: the improper terminal detection surface is angled such that if a terminal for insertion into the connector is not fully engaged and the improper terminal detection surface contacts a surface of the terminal, the improper detection surface is flush with the surface of the terminal. the additional terminal blocking offset surface; a TPA anti-stubbing feature; an improper terminal detection surface disposed between the additional terminal blocking offset surface and the TPA anti-stubbing feature; and a TPA cavity guide disposed adjacent to the improper terminal detection surface; characterised in that: the improper terminal detection surface is angled such that if a terminal for insertion into the connector is not fully engaged and the improper terminal detection surface contacts a surface of the terminal, the improper detection surface is flush with the surface of the terminal.