First, remove each wire connector one by one, check whether there is rust and dirt on the connector terminals, and clean up the rust and dirt. Then check whether the terminal piece is loose or damaged, whether the terminal is firmly fixed, and there should be no looseness when pulling gently. Conversely, if the plug terminal in one of the socket holes is easier to pull out than the other socket holes, the socket hole may cause a failure of poor contact in use.

Precautions when checking

     (1) The inspection of the connector must be carried out with the ignition lock closed, otherwise the related parts will be burned out due to self-induction.

    (2) When removing the wire connector, pay attention to loosening the locking spring or pressing the lock button, and do not pull it hard. When reassembling, insert the connector to the end and lock it.

    (3) When the waterproof connector is removed and tested, care should be taken to remove the leather cover carefully, and the waterproof cover should be in place during installation, otherwise, circuit failure may be caused by water entering the connector.

     (4) When checking the connector with a multimeter, do not apply too much force to the terminal when the meter rod is inserted, so as to prevent poor contact caused by the deformation of the end piece.