February 2017 Service ManualPlatform ControlsPart No. 1259369GT S-80 • S-85 • S-80X 77Platform ControlsThe platform control box contains one printedcircuit board. The ALC-500 circuit board inside theplatform control box controls all proportionalmachine functions from the platform. The joystickcontrollers at the platform controls utilize Hall Effecttechnology and require no adjustment. Theoperating parameters of the joysticks are stored inmemory at the ECM circuit board at the platformcontrols. If a joystick error occurs or if a joystick isreplaced, it will need to be calibrated before thatparticular machine function will operate. Refer toRepair Procedure, How to Calibrate a Joystick.Each joystick controller should operate smoothlyand provide proportional speed control over itsentire range of motion.1 ALC-500 circuit board2 drive/steer joystick controller3 secondary boom up/down joystickcontroller4 primary boom up/down and turntable rotateleft/right joystick controller1-1ALC-500 Circuit BoardNote: When the ALC-500 circuit board is replaced,the joystick controllers will need to be calibrated.Refer to Repair Procedure, How to Calibrate aJoystick.How to R emove the ALC-500 Circuit Boar dHow to Remove the ALC-500Circuit Board1 Push in the red Emergency Stop button to theoff position at both the ground and platformcontrols.2 Remove the platform control box lid retainingfasteners. Open the control box lid.3 Locate the ALC-500 circuit board mounted tothe inside of the platform control box.Electrocution/burn hazard.Contact with electrically chargedcircuits could result in death orserious injury. Remove all rings,watches and other jewelry.4 Attach a grounded wrist strap to the groundscrew inside the platform control box.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.5 Carefully disconnect the wire connectors fromthe circuit board.6 Remove the ALC-500 circuit board mountingfasteners.7 Carefully remove the ALC-500 circuit boardfrom the platform control box.
