LG Therma V AHBW Series Service Manual page 60

Display
Title
code
Problem in
08 Water Tank
sensor
Problem in
13 Solar-thermal
sensor
Check Flow Chart
Unplug the sensor
on PCB(Heater)
Check the
Connector connection
Is it normal ?
Yes
Estimate the resistance
of each sensor.
Is the resistance of
the sensor
5k at 25˚C?
Yes
Plug the sensor
on PCB(Heater)
Check Point
1. Unplug the sensor on PCB(Heater).
2. Estimate the resistance of each sensor.
3. If the resistance of the sensor is 5 KΩ at 25°C, then sensor is normal.
4. If the resistance of the sensor is 0 KΩ or ∞, then sensor is abnormal. ' Change the sensor.
5. Plug the sensor on PCB(Heater) and Power ON.
6. Estimate the voltage of each sensor.
7. If the voltage of the sensor is 2.5Vdc at 25°C, then sensor is normal.
8. If the resistance of the sensor is 0 or 5Vdc, then sensor is abnormal. ' Repair or Change the PCB.
Cause of error
• Connector connection error
• Faulty PCB(Heater)
• Faulty sensor (Open / Short)
• Connector connection error
• Faulty PCB(Heater)
• Faulty sensor (Open / Short)
No
Correct connection
No
Correct connection
Check point & Normal condition
Normal resistor : 5KΩ/ at 25˚C(Unplugged)
Normal voltage : 2.5Vdc / at 25˚C(Plugged)
Refer to sensor resistance table.
Normal resistor : 5KΩ/ at 25˚C(Unplugged)
Normal voltage : 2.5Vdc / at 25˚C(Plugged)
Refer to sensor resistance table.
Estimate the Voltage
of each sensor.
Is the voltage of
the sensor 2.5Vdc
at 25˚C
Yes
Repair or Change the PCB.
Unplugged
5k
Check the resistance
- 60 -
No
Correct connection
Plugged
2.5Vdc
V
Check the voltage