April 2018 Service and Repair ManualGround ControlsPart No. 1279835GT ZX®-135/70 796-2Circuit BoardsThe ground control box contains a replaceablemembrane decal with touch sensitive buttons forvarious machine functions. The ground control boxalso contains two printed circuit boards:The LCD (Liquid Crystal Display) circuit boardis mounted to the inside of the control box lid whichcontrols the LCD display screen.The ECM circuit board is the main circuit boardfor the machine. All operating parameters andconfiguration of options for the machine are storedin the ECM memory.Note: When the ECM circuit board is replaced, themachine will need to be fully calibrated. Refer toRepair Procedure, How to Fully Calibrate theMachine.How to Remove the LCD DisplayScreen Circuit Board1 Push in the red Emergency Stop button to theoff position at both the ground and platformcontrols.2 Remove the ground control box lid fasteners.3 Open the ground control box.Electrocution/burn hazard.Contact with electrically chargedcircuits could result in death orserious injury. Remove all rings,watches and other jewelry.Component damage hazard.Electrostatic discharge (ESD)can damage printed circuit boardcomponents. Maintain firmcontact with a metal part of themachine that is grounded at alltimes when handling printedcircuit boards OR use agrounded wrist strap.4 Carefully disconnect the LCD circuit boardribbon cable from the ECM circuit board.5 Remove the LCD display circuit boardretaining fasteners.6 Carefully remove the LCD display circuit boardfrom the ground control box lid.
