When Refrigerator Room Lamp Does Not Light - Samsung RF4287HARS Service Manual

AW3 SM-EN 2011.3.31 2:56 PM 페이지91 in
TROUBLESHOOTING
4-2-10. When refrigerator ROOM Lamp does not light up
When controlling the regrigerator light with Regulator(12V) : LED LAMP
→ Applying to the FF/FZ/Mid Drawer compartment (Option)
* If the Vegetable Lamp does not work properly, check the FF compartment LED Lamp because it is
connected with the FF compartment LED Lamp in parallel. Refer to the circuit diagram to repair.
Door & MICOM State
Door
Close
Open
Door
FF
(Right and
#52
Left)
Close 0V (Low)
Open
5V (High)
IC76(FF)/IC77(FZ)/IC78(Mid Drawer) State
Micom IC76(FF)/IC77(FZ)/IC78(Mid Drawer)
0V(Low)
5V(High)
1) Measuring IC76 voltage(CN-"3" (Red)/FF LED) Measuring
IC77 voltage(CN78-"1"(Brown)/FZ LED) Measuring
IC78 voltage(CN78-"6"(White-Black)/Mid Drawer LED)
FF LED Lamp ON
MICOM(#52)
Right and Left
0V(Low)
5V(High)
MICOM State
FZ Mid Drawer
#53 #51
5V (High) 0V (Low)
0V (Low) 5V (High)
0V(Low)
11~12V(High)
PCB connector(CN78) inserted
PCB connector(CN78) output
FF LED Lamp OFF
Start
Does the No
DOOR S/W sense properly?
(Open/Close)
Yes
Check/Replace REED S/W,
Is the output No
voltage of IC01 MICOM #52
normal?
Yes
Replace/Repair the PCB
Is the output No
voltage of IC76
normal?
Replace/Rep air the PCB.
Yes
Is the MAIN No
properly?
Yes
Does the MAIN No
properly? (11~12V)
Check the connector terminal
Yes
No
Is the LED LAMP
connected properly?
Yes
No
Is the LED LAMP normal?
Yes
Replace LED LAMP
Normal
CN76-"12"(Purple) (FF Door Switch)
Close
Open
91
Magnet ASS' Y
Repair IC76
Check the wire
Re-insert the connector
Replace PCB
Check the
connector terminal
Typical PCB Ground REG1 Heater Sink