4–3 T-3544.1.2 Display ModuleThe display module (Figure 4.3) consists of two five digit displays and seven indicator lights.The indicator lights include:1. COOL - White or Blue LED: Energized when the refrigerant compressor is energized.2. HEAT - Orange LED: Energized to indicate heater operation in heat mode, defrost mode, or dehumidification.3. DEFROST - Orange LED: Energized when the unit is in defrost mode.4. IN RANGE - Green LED: Energized when the controlled temperature probe is within specified tolerance ofset point.NOTEThe controlling probe in perishable range will be the SUPPLY air probe and the controlling probe infrozen range will be the RETURN air probe.5. ALARM - Red LED: Energized when there is an active or an inactive shutdown alarm in the alarm queue.6. SUPPLY - Yellow LED: Energized when the supply air probe is used for control. When this LED is illumi-nated, the temperature displayed in the AIR TEMPERATURE display is the reading at the supply air probe.This LED will flash if dehumidification is enabled.7. RETURN - Yellow LED: Energized when the return air probe is used for control. When this LED is illumi-nated, the temperature displayed in the AIR TEMPERATURE display is the reading at the return air probe.This LED will flash if dehumidification is enabled.Figure 4.3 Display Module4.1.3 ControllerCAUTION!Do not remove wire harnesses from controller modules unless you are grounded to the unitframe with a static safe wrist strap.CAUTION!Unplug all controller module wire harness connectors before performing arc welding on anypart of the container.NOTEDo not attempt to use an ML2i PC card in an ML3 equipped unit. The PC cards are physically differentand will result in damage to the controller.NOTEDo not attempt to service the controller modules. Breaking the seal will void the warranty.COOL HEAT DEFROST IN RANGE ALARM SUPPLY RETURNSETPOINT/Code AIR TEMPERATURE/Data
