Farad Digital
Farad Digital
Repairing Samsung 153V Lcd Monitor With Dim Display Problem
One of the common problems in Samsung 153v LCD Monitor was display dim. If you get closer to the screen and begin to observe the display under dark environment you actually could see the display but it was very dim. If you press the front panel button, the on screen display (OSD) would appeared and this proof that the main board, driver board and LCD panel is working and the problem is in the inverter board. The function of inverter board is to generate an ac wave from dc voltage to power up the lamps which was located at the top and bottom of the LCD Monitor. If the inverter board has problems it would not light up the lamps and what you could see only a dim display.
I still could recall when I first encountered such problems long time ago and because of lack of information, I could not solve it. I did call up my repair friends to asked about the solution but no one able to give me an answer. Even if you surf the internet for “Samsung 153V LCD Monitor dim display repair”, you would not find it. Due to this I have to do my own research to find the answer and I’ve never give up. Winston Churchill once said “Never, never, never give up”. I’m releasing the solution only to my loyal members or subscribers only-thanks for your support.
Let’s start now! Once the cover and the internal aluminum casing were opened I saw two bulged filter capacitors at the secondary side of switch mode power supply. The value was 470 and 1000 microfarad 25 volts. I saw four more electrolytic capacitors located at the inverter board have changed color and the value was 47 micro farad 25 volts. Browsing through the whole board with my ESR meter I found another capacitor faulty (220 uf 25 volts) which was near the fuse (3amp). Since this capacitor was located at the same line with the fuse, I presumed that the fuse may give way as well. True enough, checking the fuse with an ohmmeter revealed that it has open circuit.
Now, the real problem faced by many electronic repairers who deals with this model was, after replacing all of the components above the LCD Monitor still would not work-it’s still dim! First you have to ask yourself why the fuse blown? Could it be caused by the defective capacitors or something shorted beyond the fuse line? The nearest circuit to the fuse was the start circuit that consisted of a pair of NPN and PNP digital transistor (4k7 +4k7 resistor built into the transistor). Some other LCD monitor designed used the combination of C945 and A733 in start circuit. By the way the part number for Samsung 153V start circuit transistors were the A6J (PNP digital transistor) and the A8J (NPN digital transistor) as shown in the picture.
Sometimes only these transistors have problems (shorted) that caused the fuse to blow but in the above case both digital transistors are tested okay. Since both transistors were working, now the concentration have to be in the four ic’s that drive the high voltage transformers because the 12 volts voltage was supplying to each of these ic’s. These 4 ic’s have many part numbers and the most common one that the manufacturer used was 4532m. Some board used the AD4E10 and BBD3N13 part number. At the moment it is quite hard to get the datasheet or technical specification for this number even from the web search.
Do you know what is inside these IC’s? It is actually a pair of P-channel and a N-channel mosfet built into it. And do you know that it can be test with a meter? Yes, if you use the Peak atlas component analyzer, it would prompt to you the result. From the result what you get are N channel FET located at pin 1 (source), pin 2 (gate), pin 7 & 8 (drain and both pins joint together internally). As for P channel FET, pin 3 (source), pin 4 (gate) and pin 5 & 6 (drain and both pins joint internally). From the above test I found two of these ic’s have shorted. Replacing these two shorted IC with the capacitors and fuse put the LCD Monitor back to life!
One more thing I would like to share on this model was that the inverter PWM IC BIT1305 was quite robust and rarely gave problem.
About the Author
Find out more at the links below. You will be very surprised to discover that LCD and Electronic Component Repairs can make thousands of dollars even for a novice. You can find out the repairing secrets.
Find out How to Repair Any LCD Monitor - It is a breeze!
Learn about Secrets of Electronic Repairs.
Is this subwoofer compatible with my Jeep Laredo?
12" jensen subwoofer which has a blaupunkt speaker in it, and attatched to the back is American Pro Mosfet Amp 4 channel 1000 watt Amp w/ 24DB Crossover, and strapped to the side is a 1.0 Farad Capacitor with Digital Display.
Could I hook that setup up in my jeep grand cherokee laredo 2000?
Yeah you can hook it up to your jeep. You can put that in any vehicle. Just make sure the wiring is done correctly. Should sound good being in an SUV.
Farad Digital
Condensateur CONDO CAPA 2 FARAD DIGITAL TOXIC TOX - 2000
|
|
PYLE 2.8 FARAD DIGITAL CAPACITOR $30.87 2.8 Farad Digital Power Capacitor |
|
|
PYLE 1.8 FARAD DIGITAL CAPACITOR $29.97 1.8 Farad Digital Power Capacitor |
|
|
2 FARAD HYBRID DIGITAL CAPACITO $149.73 2 Farad Hybrid Digital Capacitor |
|
|
LEGACY 1.7 FARAD CAPACITOR $28.45 1.7 Farad Digital Power Capacitor |
|
|
LEGACY 3 FARAD CAPACITORS $38.61 3.0 Farad Digital Power Capacitor |
|
|
PYLE 5 FARAD CAPACITORS $44.5 5.0 Farad Digital Power Capacitor |
|
|
3.5 FARAD CAPACITOR RED $37.59 3.5 FARAD CAPACITOR w/DIGITAL VOLTAGE DISPLAY |
|
|
Power Acoustik 1.5 Farad Digital Pwr Capacitor $27.99 Power Acoustik 1.5 Farad Digital Pwr Capacitor |
|
|
Boss 3.5 Farad Capacitor Digital Voltagemeter $44.99 BOSS 3.5 FARAD CAPACITOR DIGITAL VOLTAGEMETER |
|
|
Triangle 3.0L-3 Farad Digital Power Capacitor (Black) $93.09 High performance triangle 3 farad digital power capacitor. |
|
|
Planet Audio Pc20F Capacitor 20 Farad $122.81 DIGITAL VOLTAGE DISPLAY ; BLUE ILLUMINATION ; 20 FARAD |
|
|
1.5 Farad Digital Pwr Capacitor Digital Display Chrome Plated $32.99 1.5 FARAD DIGITAL PWR CAPACITOR DIGITAL DISPLAY CHROME PLATED |
|
|
MobileSpec MSCAPD 1 Farad Digital Capacitor $49.53 1 Farad. Red Digital Voltage Display. 20Volt DC Surge. Contemporary Satin Finish. Manufactured to the Highest Quality Available. Satisfaction Ensured. |
|
|
Boss CAP35S 3.5 Farad Capacitor Digital Voltage Meter $56.03 3.5 Farad capacitor digital voltage meter. Satisfaction ensured. Manufactured to the highest quality available. |
|
|
Boss CAP2S 2 Farad Capacitor Digital Voltage Meter $49.4 2 Farad capacitor with digital voltage meter. Color: Silver finish. Dimensions: 14 x 7 x 4. Satisfaction ensured. |
|
|
Boss CAP20 20 Farad Capacitor Black Chrome $114.95 Digital Voltage Meter. Black Chrome. Active Light Show 20 Farad. Dimensions: 9.7 x 4.2 x 12.9. Satisfaction ensured.F |
|
|
Power Acoustik OWPC15F 1.5 Farad Power Capacitor $46.32 1.5 Farad. Digital Display. 1216 Volts DC. Chrome Plated. Digital Red 8 Segment LED's. Mounting Brackets. Digital Display. Double Clamp Blister Packaging. |
|
|
Pyle PLCAPE18 1.8 Farad Digital Power Capacitor $49.11 1.8 Farad Digital Display Power Capacitor. Capacitance plusmn; 5. 2024 Volt Surge 105oC. Blue Digital Display and blue LED flash. Strong Finishing For A Better Installation Result. 1 Pair Clear Brackets Included. Chrome Plated Post Kits. DC 12 24 volt. Electronic Polarity Protection Circuit. Over Voltage Protection Circuit. Includes Mounting Charging Hardware. Aluminum Brushed Case. Dimensions: 8.66 H 2.99 W |
|
|
Pyle PLCAPE50 5.0 Farad Digital Power Capacitor $68.34 5.0 Farad Digital Display Power Capacitor. Capacitance plusmn; 5. 2024 Volt Surge 105oC. Blue Digital Display and blue LED flash. Strong Finishing For A Better Installation Result. 1 Pair Clear Brackets Included. Chrome Plated Post Kits. DC 12 24 volt. Electronic Polarity Protection Circuit. Over Voltage Protection Circuit. Includes Mounting Charging Hardware. Aluminum Brushed Case. Dimensions: 8.86 H 3.5 W |
|
|
Pyle PLDCP17 1.7 Farad Digital Power Capacitor $50.13 1.2 Farad Digital Display Power Capacitor. Capacitance plusmn; 5. 2024 Volt Surge 105oC. Strong Finishing For A Better Installation Result. 1 Pair Clear Brackets Included. Chrome Plated Post Kits. Electronic Polarity Protection Circuit. Over Voltage Protection Circuit. Includes Mounting Charging Hardware. Aluminum Brushed Case. Red Digital Display and blue LED flash. PVC sleeve and blister package. DC 12 24 volt. Dimensions: 8.66 H x 2.99 W |
|
|
Pyle 1.7 Farad Digital Capcitor PLDCP17 $50.13 1.2 Farad Digital Display Power Capacitor. Capacitance 5. 2024 Volt Surge 105oC. Strong Finishing For A Better Installation Result. 1 Pair Clear Brackets Included. Chrome Plated Post Kits. Electronic Polarity Protection Circuit. Over Voltage Protection Circuit. Includes Mounting Charging Hardware. Aluminum Brushed Case. Red Digital Display and blue LED flash. PVC sleeve and blister package. DC 12 24 volt. Dimensions: 8.66 H x 2.99 W |
|
|
Pyle 1.8 Farad Digital Capacitor PLCAPE18 $49.11 1.8 Farad Digital Display Power Capacitor. Capacitance 5. 2024 Volt Surge 105oC. Blue Digital Display and blue LED flash. Strong Finishing For A Better Installation Result. 1 Pair Clear Brackets Included. Chrome Plated Post Kits. DC 12 24 volt. Electronic Polarity Protection Circuit. Over Voltage Protection Circuit. Includes Mounting Charging Hardware. Aluminum Brushed Case. Dimensions: 8.66 H 2.99 W |
|
|
Pyle 5.0 Farad Digital Power Capacitor PLCAPE50 $68.34 5.0 Farad Digital Display Power Capacitor. Capacitance 5. 2024 Volt Surge 105oC. Blue Digital Display and blue LED flash. Strong Finishing For A Better Installation Result. 1 Pair Clear Brackets Included. Chrome Plated Post Kits. DC 12 24 volt. Electronic Polarity Protection Circuit. Over Voltage Protection Circuit. Includes Mounting Charging Hardware. Aluminum Brushed Case. Dimensions: 8.86 H 3.5 W |
How To Repair Dell E153Fpc LCD Monitor With Shutdown Problem
Repairing the DELL E153Fpc LCD Monitor with the complaint of display shutdown after few seconds (power LED still on) was not difficult. Normally when this type of problem happens, we would first suspect the inverter board, then the filter capacitors and lastly the main board. A defective in one of the lamps and a faulty TL1451AC PWM IC or inverter ic may caused the display to shutdown as well. If the lamp is defective, it will send a feedback to pin 3 or 14 of TL1451AC IC and caused it to stop producing output signal thus the display just shut off once you switch it on. The power board is using a SG6841D pwm ic and a FQPF7N80 power fet . If this power section blow, it is quite easy to troubleshoot because it has fewer components. You can also use other part numbers to substitute the power fet.
As usual, after opening up the cover, I would first check for any burnt components, loose connector, cracked board, dry joints and etc before doing the voltage test. As for the lamps, I would check it last because lamps were seldom spoilt. Upon scanning for any bad components before starting the voltage test, I found a filter capacitor that had turned into darker color. Using the ESR meter revealed the ESR ohm has shoot up to 12 ohms. This filter capacitor located at C922 with the value of 1000 micro farad 16 volt. If you don’t have the ESR meter you can always use the digital capacitance meter. The value that I got from measuring the bad capacitor was 57 microfarad. If you don’t have ESR meter, make sure you get one-it’s fast and accurate.
Now, the question is why a filter capacitor can cause the display to shutdown? If you carefully see the picture, I’ve drawn the yellow path to show you how the voltage is flowing. By the way, the voltage at the bad filter capacitor line is 12 volt. The voltage passed through a SMD transistor in the start circuit and flow straight to pin 9 (VCC) of TL1451AC IC. In order to let the 12 volt to flow through the transistor and reach the vcc pin of the ic, first, a ‘on’ signal must be sent from the main board to trigger the transistor. If no signal send to the transistors (off signal), both transistors can’t be turned on and no voltage will follow through the ic. Thus if the main board or any of the start circuit components spoilt, there will be power but no display because the TL1451AC would not send signal to the Royer type L, C resonant and boost circuit, so no high voltage produced by the high voltage transformer and this will lead to no display.
In the above case, the LCD Monitor display shutdown was due to the ripple because of the bad filter capacitor. The ripple caused the TL1451AC IC to be unstable and eventually shutdown the output signal. Replacing only the filter capacitor solved the DELL E153Fpc LCD Monitor shutdown problem.
Conclusion, don’t always presumed that LCD Monitor is very tough or difficult to repair. From the above article, you could see that the caused of the shutdown problem was only a bad capacitor. If you fully understood how LCD Monitor works, then chances for you to successfully repair the monitor is very high but again it depends on the availability of spare parts. If you ever come across any LCD Monitor sent to you for repair for the first time, go ahead and start troubleshoot it. Who knows one day LCD Monitor repair could become one of the major source of income to you and your business.
About the Author
Find out more at the links below. You will be very surprised to discover that LCD and Electronic Component Repairs can make thousands of dollars even for a novice. You can find out the repairing secrets.
Find out How to Repair Any LCD Monitor - It is a breeze!
Learn about Secrets of Electronic Repairs.
Farad Digital