An electrical connector has a housing, a circuit board, harness terminals, and contact terminals. The housing has a hole and a lid. The circuit board is detachably disposed in the hole. If the circuit board is broken down, the lid is opened and the circuit board is removed from the hole. A new circuit board is then disposed on the terminals in the hole. The lid is closed so that the terminals are elastically deformed and the electrodes of the circuit board are electrically connected to the terminals.