A. Check the contact and connection terminal 1,2,3 on counter panel The failure on main control panel or terminals
A1. Check the terminal 5,6 on main control panel J1 with multi-meter to see the level output;
A2. If no level output, check the chip connection with power off, if still no display, it shall be the failure of main control panel, which shall be repaired or changed;
A3. If it has level output, check the connection between terminal 5,6 on main control panel J1 and terminal 4 on indication boardFailure on direction indication circuit boardA. If above checking still can not solve the problem, it shall be the problem of direction indication board which shall be repaired or changed