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.

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.

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.

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.

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.

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.

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.

When Key does not operate.
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.

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.

Panasonic SA PM86 DVD stereo system how to enter the service mode, firmware update, power amp and power supply schematic, system reset

Panasonic SA-PM86DGCS, SA-PM86DEE DVD Stereo System

This model’s mechanism unit is DLS6

RMS Output Power THD 10%  80 W per channel (3 Ω), 1 kHz

Total RMS Dolby Digital Mode  80 W per channel (3 Ω), 1 kHz

PMPO Output Power  1800 W

Speakers: SB-PM86EG-K

Video system PAL625/50, PAL525/60, NTSC

Power consumption 95 W AC 230 V, 50 Hz (EE) - AC 220 to 240 V, 50/60 Hz (GCS)

Before Repair and Adjustment Disconnect AC power, discharge Power Supply Capacitors C2207, C2210, C2211, C2212, C2742, C5105, C5106, C5916, C5917,
C5938, C5562, C5954, C5979 and C5993 through a 10Ω, 1W resistor to ground.  DO NOT SHORT-CIRCUIT DIRECTLY (with a screwdriver blade, for instance), as this may destroy solid state devices.
After repairs are completed, restore power gradually using a variac, to avoid over current.

Current consumption at AC 220 - 240 V, at 50/60 Hz in NO SIGNAL mode (at volume min) should be ~500 mA. (GCS)

Current consumption at AC 230 V 50 Hz in NO SIGNAL mode (at volume min) should be ~500 mA. (EE)

Protection

The protection circuitry may have operated if either of the following conditions are noticed:
• No sound is heard when the power is turned on.
• Sound stops during a performance.
The function of this circuitry is to prevent circuitry damage if, for example, the positive and negative speaker connection wires are "shorted", or if speaker systems with an impedance less than the indicated rated impedance of the amplifier are used.
If this occurs, follow the procedure outlines below:
1. Turn off the power.
2. Determine the cause of the problem and correct it.
3. Turn on the power once again after one minute.
Note:
When the protection circuitry functions, the unit will not operate unless the power is first turned off and then on again.

Do not disassemble the pickup unit, since radiation from exposed laser diode is dangerous.
2. Do not adjust the variable resistor on the pickup unit. It was already adjusted.
3. Do not look at the focus lens using optical instruments.
4. Recommend not to look at pickup lens for a long time

Service Mode

The service modes can be activated by pressing various button combination on the main unit and remote control unit.
Below is the summary for the various modes for checking

An error code will be canceled if a power supply is turned OFF.
1: CPPM is the copy guard function beforehand written in the disk for protection of copyrights.
2: CEC is the consumer electronic control used for high-level user control of HDMI-connected devices.
3: HDCP is the specification developed to control digital audio & video contents transmission for DVI or HDMI connections

By pressing various button combinations on the main unit and remote control unit, you can activate the various service modes for checking.

Due to the limitations of the no. characters that can be shown on the FL Display, the “FL Display” button on the remote control unit can be used to show the two display pages. (Display 1 / Display 2).

Optical Pick-up Self-Diagnosis

The optical pickup self-diagnosis function and tilt adjustment check function have been included in this unit. When repairing, use the following procedure for effective self-diagnosis and tilt adjustment. Be sure to use the self-diagnosis function before replacing the optical pickup when "NO DISC" is displayed. As a guideline, you should replace the optical pickup when the value of the laser drive current is more than the specified value.

[Press the power button to turn on the power, and check the value within three minutes before the unit warms up. (Otherwise, the result will be incorrect.)]

DVD Self Diagnostic Function-Error Code

Sales Demonstration Lock Function
This function prevents discs from being lost when the unit is used for sales demonstrations by disabling the disc eject function.
"LOCKED" is displayed on the unit, and ordinary operation is disabled.

Prohibiting removal of disc
1. Select the DVD/CD function.
2. At POWER ON condition, press and hold down the STOP button and the power button on the main unit for at least three seconds. (The message, “LOCKED” appears when the function is activated.)

[OPEN/CLOSE button is invalid and the main unit displays “LOCKED” while the lock function mode is entered]

Prohibiting operation of selector and disc
1. Select the DVD/CD function.
2. At POWER ON condition, press and hold down the PLAY button and the power button on the main unit for at least three seconds. (The message, “LOCKED” appears when the function is activated.)

The lock can be cancelled by the same procedure as used in setting. ("UNLOCKED" is displayed on cancellation. Disconnecting the power cable from power outlet does not cancel the lock.)

Recovery after the DVD player is repaired
• When the FLASH ROM IC or DVD Module P.C.B. is replaced, carry out the recovery processing to optimize the drive.  Playback the recovery disk to process the recovery automatically.
• Recovery disc (Product number: RFKZD03R005) [SPG]
• Performing recovery process
1. Load the recovery disc RFKZD03R005 on to the player and run it.
2. Recovery is performed automatically. When it is finished, a message appears on the screen.
3. Remove the recovery disc.
4. Turn off the power.
5. Initialize the player.

Firmware version-up of the DVD player
• The firmware of the DVD player may be renewed to improve the quality including operability and playability to the substandard discs. Processing to optimize the drive.
The recovery disc has also firmware version-up.
• After version-up, recovery processing is executed automatically.
• Part number of the recovery disc for version-up will be noticed when it is supplied.
• Updating firmware
1. Load the recovery disc on to the player and run it.
2. Firmware version of the player is automatically checked. Appropriate message appears whenever necessary.
3. Using remote controller´s cursor key, select whether version updating is to be done or not. (Selection of Yes/No)
4. a. If Yes is selected, version updating is performed.
b. If No is selected, only recovery is performed.
5. a. When updating is finished, remove the disc according to the message appearing on the screen.
b. Remove the disc according to the message appearing on the screen.
6. Turn off the power.

 [If the AC power supply is shut out during version-up due to a power failure, the version-up is improperly carried out.  In such a case, replace the FLASH ROM IC and carry out the version-up again.]

DVD Module P.C.B. Reset
• When after replacing FLASH ROM IC or DVD Module P.C.B., FL displays error code “ DVD F897”. This means the unit is not initialized properly and the following process needs to be carry out.
• Procedures:
1. Press _>10 on remote control while pressing “STOP” button on main unit. (To enter into initialization)

2. FL display show “INIT”
3. While still pressing “STOP” button on main unit, press “OK” on remote control. (To reset the unit)
4. FL will display “RESET” before FL display will change to TOC reading again.
5. Power off unit. Unplug the AC cord.
6. Power on the unit. It should be no problem. If problem persist check on the DVD Module P.C.B. or FLASH ROM IC.

Power amplifier and main power schematic

Power clamp circuit

Power Transformer circuit