Samsung RF23HT Series Service Manual page 100

TROUBLESHOOTING
4-2-13. When refrigerator ROOM Lamp does not light up
When controlling the refrigerator light with Regulator(12V) : LED LAMP
Applying to the F/R Room compartment (Option)
→
* If the Vegetable Lamp does not work properly, check the R compartment LED Lamp because it is connected with
the R compartment LED Lamp in parallel. Refer to the circuit diagram to repair.
Door & MICOM State
Door
Close
Open
Door
(Right and
Left)
Close 0V (Low)
Open
5V (High)
Q715(R)/Q714(F) State
IC
0V(Low)
5V(High)
*The Filler lighting LED Lamp is not working.
1) It is connected with the lamp in the fridge and if the lamp in the fridge is not
working, please consult the troubleshooting guide for checking the lamps.
2) If the lamps are working properly except the Filler lighting LED Lamp, please
disassemble the Top Table and check according to the following procedure.
3) Please turn on the power and check the DC Voltage with TP4 (Red), TP5
(Black, GND) on PBA where the voltage drop occurs.
- If the voltage is measured at 11V (±2V), please follow the procedure as
described in step 4.
- If you fail to measure the voltage, please check if the connectors and wires
are connected properly.
4) Please turn on the power and check the DC Voltage with TP1 (Red), TP5
(Black, GND) on PBA where the voltage drop occurs.
- If the voltage is measured at 10V (±2V), please check if the connectors and
wires are connected properly and replace the Filler lighting LED if necessary.
- If you fail to measure the voltage, please replace the PBA.
1) Measuring output voltage
- Measuring the voltage of PCB typical Ground REG1-GND and Q715(R)
voltage( CN78-"3"(Red)/R LED), Q714 voltage (CN78-"1"(Brown)/F LED)
R LED Lamp ON
MICOM(#59)
Right and Left
0V(Low)
5V(High)
MICOM State
R F
#59 #58
0V (High)
5V (Low)
Q715(R)/Q714(F)
0V(Low)
11~12V(High)
R LED Lamp OF
Start
Does the
DOOR S/W sense properly?
(Open/Close)
Yes
Is the output
voltage of IC01 MICOM #59
normal?
Yes
Is the output
voltage of Q715
normal?
Yes
Is the MAIN
PCB connector(CN78) inserted
properly?
Yes
Does the MAIN
PCB connector(CN78) output properly?
(11~12V)
Yes
Is the LED LAMP
connected properly?
Yes
Is the LED LAMP no mal?
Yes
Normal
Checking method of Door switch voltage.
- Measuring voltage of CN76-"12")(Purple)
typical Ground REG1-GND
Close
Open
100
No
Check/Replace REED S/W,
Magnet ASS`Y
No
Replace/Repair the PCB
No
Replace/Rep air the PCB.
Repair Q715
No
Check the wire
Re-insert the connector
No
Check the connector terminal
Replace PCB
No
Check the
connector terminal
No
Replace LED LAMP
PCB Typical Ground
REG1-GND
↔
PCB