1. Neither the main control lock nor the sub-control lock does not act.
    1) Check the connection of power wire and the fuse.
    2) Check the plug of control box.
    3) Replace the control box to test if necessary.

2. Main control lock disfunction.
    1) Check the matching color-coded wires to confirm whether they are matched correctly, or there is a short way.
    2) Check the mechanism construction to confirm whether all parts are complete
    3) Check the correct moving stroke and installed parts directions.
    4) Replace the sub-control lock to test if necessary.

3. Sub-control lock disfuction.
    1) Check the matching color-coded wires to confirm whether they are matched correctly, or there is a short way.
    2) Check the mechanism construction to confirm whether all parts are complete.
    3) Check and identify the correct moving stroke and installed parts directions.
    4) Replace the main control lock to test, if necessary.