Thermo King SGCO 3000, Руководство пользователя

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Electrical Maintenance
83
Coolant Temperature Sensor
The coolant temperature sensor is connected to
the engine coolant system near the water pump. It
uses coolant temperature to present a variable
resistance to the controller. Test the coolant
temperature sensor if the controller records Alarm
Code 18 or 41 and the coolant temperature
appears to be normal.
Figure 45: Coolant Temperature Sensor
Sensor Test
1. Turn the unit On/Off switch to the “OFF”
position.
2. Disconnect the sensor at the plug next to the
sensor.
3. Turn the unit On/Off switch “ON”.
NOTE: Polarity must be considered when
connecting temperature sensors. If a sensor is
connected backwards, the display will show a
reading below -40 C (-40 F) or above 130 C (266
F) and record Alarm Code 101. Consult the unit
wiring diagram or schematic for correct
connections.
4. Enter the Analog Inputs submenu of the Data
Menu and scroll to the engine temperature
screen. If the display shows a reading below
-40 C (-40 F) or above 130 C (266 F) check
the sensor wiring, the sensor polarity, and test
the controller.
5. Using a digital voltmeter, check the voltage at
the sensor plug connected to the controller.
The voltage must be from 2.33 to 3.98 Vdc.
a. If the voltage is correct, disassemble and
inspect the coolant sensor plug. Replace
the sensor if there are no broken wires or
pushed pins in the plug.
b. If the voltage is incorrect, recheck the
voltage at the same circuit at pins 13
(positive) and 14 (negative) of the J1
connector on the microprocessor PC
board. The voltage must be from 2.33 to
3.98 Vdc. If the voltage is correct at the
controller, the problem is in the wiring.
Continuity test the wire harness circuits. If
the voltage is incorrect again, the
controller is defective. Test the controller.
AJA2063
AJA2061