Daewoo 42 and 46 inch LCD TV – service mode and adjustments, troubleshooting procedure - CHASSIS : SL-701T
Daewoo DLT-42U1GMB, DLT-42G1LTBD, DLT-46U1UMB, DLT-46U1STB - LCD TV - How to enter the service mode, Troubleshooting.
SERVICE MODE
Using
the Service Remote controller, you can enter service mode directly. [SERVICE
REMOCON : R-34SVC(S/N:48B3034SVC)]
EEPROM initial DATA
Description of SERVICE MODE ITEM
A. S1(1): Heat-Run Key
B. S2(2): Gumi Channel Map Write
C. S3(3): Volume Test. => This key can check sound
D. S4(4): EDIE WRITE => Using this key, you can update EDID data below method.
1. Connect two jumpers (P502) vertically.
2. Press "S4" key and then, TV set display "EDID WRITE OK" upper left of screen.
3. If EDID writing is fail, TV set display "EDID Write Error" upper left of screen.
4. After EDID write, remove jumper.
A. S1(1): Heat-Run Key
B. S2(2): Gumi Channel Map Write
C. S3(3): Volume Test. => This key can check sound
D. S4(4): EDIE WRITE => Using this key, you can update EDID data below method.
1. Connect two jumpers (P502) vertically.
2. Press "S4" key and then, TV set display "EDID WRITE OK" upper left of screen.
3. If EDID writing is fail, TV set display "EDID Write Error" upper left of screen.
4. After EDID write, remove jumper.
E.
S5(5): PANEL TEST. => Using this key, you can test problem of PANEL, as
confirm white pattern, red pattern,blue pattern, green pattern.
F. S6(6): PICTURE TEST => Using this key, you can test brightness, contrast and color.
G. S7(7): DEMPOL CHANNEL MAP WRITE
H. S8(8): EEPROM Erase and White Balance adjustment. => Using this key, you can erase EEPROM data and adjust White balance.
I. S9(9): Device control. => This key only use for R&D.
J. S10(10): Option key. => Using this key, you can adjust SSC, Dimming, Panel Type, Control key and etc.
K. S11(11): I2C STOP key. => This key only use for R&D.
L. S12(SLEEP): Shipping key. => Using this key, you can set up at shipping mode.
F. S6(6): PICTURE TEST => Using this key, you can test brightness, contrast and color.
G. S7(7): DEMPOL CHANNEL MAP WRITE
H. S8(8): EEPROM Erase and White Balance adjustment. => Using this key, you can erase EEPROM data and adjust White balance.
I. S9(9): Device control. => This key only use for R&D.
J. S10(10): Option key. => Using this key, you can adjust SSC, Dimming, Panel Type, Control key and etc.
K. S11(11): I2C STOP key. => This key only use for R&D.
L. S12(SLEEP): Shipping key. => Using this key, you can set up at shipping mode.
Trouble Shooting
When “No signal” in RF, SCART1,SCART2,AV3
1) First check if other inputs are working. =>If other inputs are not working, replace MAIN PCB.
2) Checking waveform with Color Bar Pattern (Using the oscilloscope).
-Main TP (RF): CC613 near IC601 (Top).
-Main TP(SCART1): LC019 near JP208 (Top).
-Main TP(SCART2): LC213 near JP207 (Top).
-Main TP(AV3): RC055 near P240. => If all TP signal does not appear, replace MAIN PCB.
1) First check if other inputs are working. =>If other inputs are not working, replace MAIN PCB.
2) Checking waveform with Color Bar Pattern (Using the oscilloscope).
-Main TP (RF): CC613 near IC601 (Top).
-Main TP(SCART1): LC019 near JP208 (Top).
-Main TP(SCART2): LC213 near JP207 (Top).
-Main TP(AV3): RC055 near P240. => If all TP signal does not appear, replace MAIN PCB.
When “No Signal” in Y/C signal (S-Video)
1) First check if other inputs are working. =>If other inputs are not working, replace MAIN PCB
2) Checking waveform with Color Bar Pattern (Using the oscilloscope).
-Main TP(Y signal): RC053 near P240.
-Main TP(C signal): RC050 near P240.
=> If all TP signal does not appear, replace MAIN PCB.
1) First check if other inputs are working. =>If other inputs are not working, replace MAIN PCB
2) Checking waveform with Color Bar Pattern (Using the oscilloscope).
-Main TP(Y signal): RC053 near P240.
-Main TP(C signal): RC050 near P240.
=> If all TP signal does not appear, replace MAIN PCB.
When “No Signal” in Y/Pb/Pr signal (Component)
1) First check if other inputs are working. =>If other inputs are not working, replace MAIN PCB.
2) Checking waveforms with Color Bar Pattern (Using the oscilloscope).
-Main TP (COMP_Y): RC233 near JP211 (Top).
-Main TP (COMP_Pb): RC234 near JP211 (Top).
-Main TP (COMP1_Pr): RC235 near JP211 (Top).
=> If all TP signal does not appear, replace MAIN PCB.
1) First check if other inputs are working. =>If other inputs are not working, replace MAIN PCB.
2) Checking waveforms with Color Bar Pattern (Using the oscilloscope).
-Main TP (COMP_Y): RC233 near JP211 (Top).
-Main TP (COMP_Pb): RC234 near JP211 (Top).
-Main TP (COMP1_Pr): RC235 near JP211 (Top).
=> If all TP signal does not appear, replace MAIN PCB.
When “No Signal” in PC
1) First check if other inputs are working. =>If other inputs are not working, replace MAIN PCB.
2) Checking waveforms with Color Bar Pattern (Using the oscilloscope).
-Main TP(R signal): RC629 near IC601(Top).
-Main TP(G signal): RC627 near IC601 (Top).
-Main TP(B signal): RC628 near IC601 (Top).
-Main TP(H-Sync): RC630 near IC601 (Top), -Main TP(V-Sync): RC640 near IC601 (Top).
=> If all TP signal does not appear, replace MAIN PCB.
1) First check if other inputs are working. =>If other inputs are not working, replace MAIN PCB.
2) Checking waveforms with Color Bar Pattern (Using the oscilloscope).
-Main TP(R signal): RC629 near IC601(Top).
-Main TP(G signal): RC627 near IC601 (Top).
-Main TP(B signal): RC628 near IC601 (Top).
-Main TP(H-Sync): RC630 near IC601 (Top), -Main TP(V-Sync): RC640 near IC601 (Top).
=> If all TP signal does not appear, replace MAIN PCB.
When “No Signal” in HDMI
1) First check if other inputs are working. =>If other inputs are not working, replace MAIN PCB.
2) Checking waveform with Color Bar Pattern (Using the oscilloscope).
-Main TP (RC672, RC671, RC670, RC668, RC667, RC666, RC665) near IC601. => If all TP signal does not appear, replace MAIN PCB.
1) First check if other inputs are working. =>If other inputs are not working, replace MAIN PCB.
2) Checking waveform with Color Bar Pattern (Using the oscilloscope).
-Main TP (RC672, RC671, RC670, RC668, RC667, RC666, RC665) near IC601. => If all TP signal does not appear, replace MAIN PCB.
When
Key does not operate.
42G1 : replace the key PCB.
42/46 U1 : replace the touch button.
42G1 : replace the key PCB.
42/46 U1 : replace the touch button.
Trouble diagnosing or repairing.
A. Trouble
diagnosing and repairing of set mean find out which PCBs or blocks are not working
and replace them with new PCBs. Repairing the broken PCBs are not necessary.
Keep the broken PCBs and return them to service center or R&D center.
B. This TROUBLE DIAGNOSIS list only contains representative and simple PCB trouble diagnosis and Module Exchange method. Therefore, if you find Sets that are difficult to diagnosis or to repair, contact R&D center.
C. Basic TROUBLE DIAGNOSIS process.
B. This TROUBLE DIAGNOSIS list only contains representative and simple PCB trouble diagnosis and Module Exchange method. Therefore, if you find Sets that are difficult to diagnosis or to repair, contact R&D center.
C. Basic TROUBLE DIAGNOSIS process.
D.
Required equipment for trouble diagnosis [Digital Multimeter]
User Mode: measure DC VOLTAGE, DIODE VOLTAGE, SHORT/OPEN TEST
-Screwdriver or electric screwdriver, plastic adjusting tool
-Oscilloscope (for detailed examination only)
E. Each BLOCK operations explained here, but these are for reference only and utilizing them to repair PCBs is not necessary.
F. Before replacing PCBs, you MUST turn off the AC switch.
G. After replacing POWER, MAIN and SUB PCB, extra adjustment might be needed.
H. After the set is repaired, leave BACK COVER open for followings. Run HEATRUN for at least 30 minutes by displaying TEST PATTERN (Full White) of SERVICE MODE.
Check the screen conditions and basic functions.(Remote Controller operation etc.).
J. After BACK COVER is closed, redo HEATRUN for at least one hour with Full White input using TEST PATTERN of SERVICE MODE. Check the screen conditions and basic functions.
User Mode: measure DC VOLTAGE, DIODE VOLTAGE, SHORT/OPEN TEST
-Screwdriver or electric screwdriver, plastic adjusting tool
-Oscilloscope (for detailed examination only)
E. Each BLOCK operations explained here, but these are for reference only and utilizing them to repair PCBs is not necessary.
F. Before replacing PCBs, you MUST turn off the AC switch.
G. After replacing POWER, MAIN and SUB PCB, extra adjustment might be needed.
H. After the set is repaired, leave BACK COVER open for followings. Run HEATRUN for at least 30 minutes by displaying TEST PATTERN (Full White) of SERVICE MODE.
Check the screen conditions and basic functions.(Remote Controller operation etc.).
J. After BACK COVER is closed, redo HEATRUN for at least one hour with Full White input using TEST PATTERN of SERVICE MODE. Check the screen conditions and basic functions.
