When Refrigerator Room Lamp Does Not Light Up - Samsung RF28HMEDBSR Service Manual

TROUBLESHOOTING

4-2-11. When refrigerator ROOM Lamp does not light up

When controlling the regrigerator 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
MICOM(#28)
Door
Right and Left
Close
Open
MICOM State
FF
Door
#28
Close 0V(Low)
Open 5V(High)
IC76(R)/IC77(F) State
IC IC76(R) / IC77(F) / IC78(MID)
0V(Low)
5V(High) 11~12V(High)
1) Measuring output voltage
- Measuring the voltage of PCB typical Ground J23 JUMMPER and IC76
voltage( CN78-"3"(Red)/R LED), IC77 voltage (CN78-"1"(Brown)/F LED)
R LED Lamp ON R LED Lamp OF
0V(Low)
5V(High)
FZ(MID)
#29(#40)
0V(Low)
5V(High)
0V(Low)
PCB connector(CN78) output properly?
Start
Does the No
DOOR S/W sense properly?
(Open/Close)
Yes
Is the output No
voltage of IC01 MICOM #28
normal?
Yes
Is the output No
voltage of IC76
normal?
Yes
Is the MAIN No
PCB connector(CN78) inserted
properly?
Yes
Does the MAIN No
(11~12V)
Yes
No
Is the LED LAMP
connected properly?
Yes
No
Is the LED LAMP no mal?
Yes
Normal
Checking method of Door switch voltage.
↔
- Measuring voltage of CN76-"12")(Purple)
typical Ground J23 JUMMPER
Close
Open
96
Check/Replace REED S/W,
Magnet ASS`Y
Replace/Repair the PCB
Replace/Rep air the PCB.
Repair IC76
Check the wire
Re-insert the connector
Check the connector terminal
Replace PCB
Check the
connector terminal
Replace LED LAMP
PCB Typical Ground J23
JUMMPER
PCB