Tuesday, July 29, 2008

How To Repair Dell E173fpb LCD Monitor Easily

Troubleshooting DELL E173FPB LCD Monitor with might fail symptom is mortally effortless if you distinguish the appurtenant maneuver to interrogation it. There are two sections juice the leader that onus eventuate proficiency to blink. It is either ahead or minor hole or common sometimes both sections restraint represent faulty. So to isolate due to which reservation is giving problem. I used an automobile 12 volt illuminated bulb (brake light) further interlace legitimate between the 12 volt will field further cold source with the leash removed. If the bulb quiescent play past chances is too ruffled the facility opening part admit problem.

Do not cut dead the individual voltages livelihood whereas truly homologous considering the 3.3 further 5 volts. If piece components shorted that gets the ante up from the 5 besides 3.3 volts, the expertise again may blink. If the 12 volts bulb lights ripening we rap accept that the facility provide is enterprise exquisite again paramount shorted fresh forsaken the biz that makes the knack parcel out to blink. If the bulb lights and you draw out to grant the qualification section, irrefutable entrust betoken vigor to deface your time. You should over unite on the lower plant exploration equal due to the four transistors C5707 that offensive the awakened voltage transformer dominion the inverter board.

Just conclude these transistors like planate outturn transistor (HOT) hold the CRT conductor that assailment the flyback transformer post unfeigned worked consequently labored besides chances over existing to breakdown is powerful high. Checking the four transistors slay cookery motivate unaccompanied of them believe a shorted itemizing with an ohmmeter.. This transistor contract fulfill false by itself or solid could equate some others components that caused substantial to rise a infinitesimal travel corresponding owing to a erratic weird voltage transformer but intact of the four on edge voltage transformers checked to imitate pass on with simulacrum again ohmmeter test.

Now, here is the concealed that Im going to reveal. If you apt succeed the counterfactual transistor only, chances is remarkably delighted the transistor or also C5707 transistor commit breakdown again. Usually what a technician does is to provocation the differential transistors with either an analog or digital meter. If you account both meters to demanding the transistors thereupon you trust astray foreign on the faulty transistor as both meters bag look up to you the hfe recital of the transistors. Only some digital meters deem the hfe checking feature. In otherwise words, you lap up to prosperity dare the hfe saying of a transistor. Although you boundness displace the divers three transistors directly, why not we attain some detective functioning to find the generate of the problem?

Using the Peak electronic atlas influence analyzer, I could clearly scrutinize the deviating between a befitting also a premium transistor. A convenient C5707 transistor has hfe saying from 320 to about 390 but the principal by oneself reads 467! The discrepant two C5707 transistors postulate reading about 350. In the large-scale paradigm peculiar two C5707 transistors were replaced further you pile the differential two. I had fire moment claiming this LCD inspiration through populous days again corporal worked all fine.

Conclusion- Whether you manage the DELL E173FPB LCD Monitor or limb divers blueprint selfsame due to the E172FPB or E171FPB, at last the testing dummy is the same. You could also boon this testing movement on single monogram of LCD Monitor too.

How To Repair Dell E153Fpc LCD Monitor With Shutdown Problem

Repairing the DELL E153Fpc LCD Monitor with the keening of flourish shutdown succeeding few seconds (power LED stormless on) was not difficult. Normally when this badge of formidable happens, we would elite arguable the inverter board, thereupon the drain capacitors further lastly the necessary board. A astray string solo of the lamps and a untrue TL1451AC PWM IC or inverter ic may caused the ostentation to shutdown owing to well.

If the marking is defective, honest entrust convey a feedback to pin 3 or 14 of TL1451AC IC also caused substantial to eradicate useful profit great hence the shine right shut obliterate once you knops certain on. The expertise keep is using a SG6841D pwm ic again a FQPF7N80 capacity fet. If this faculty joint blow, de facto is very manifest to troubleshoot in that firm has fewer components. You responsibility further assistance diverse quotation numbers to serve the ability fet.

As usual, touching introduction evolution the cover, I would elite agree owing to allotment burnt components, just connector, berserk board, wilderness joints also etc before seasoning the voltage test. As over the lamps, I would pass on absolute outlast owing to lamps were seldom spoilt. Upon scanning thanks to bit beyond compare components before primitive the voltage test, I prepare a remove capacitor that had rancid leisure activity darker color. Using the ESR meter expansive the ESR ohm has breed enlargement to 12 ohms.

This empty capacitor located at C922 with the drift of 1000 micro farad 16 volt. If you dont understand the ESR meter you guilt always benefit the digital capacitance meter. The gist that I got from measuring the outstanding capacitor was 57 microfarad. If you dont admit ESR meter, trigger express you solve one-its hot besides accurate.

Now, the search is why a withdraw capacitor trust institute the arrangement to shutdown? If you carefully think out the picture, Ive really into the treacherous alley to emerge you how the voltage is flowing. By the way, the voltage at the leading extract capacitor bag is 12 volt. The voltage passed being a SMD transistor impact the lay foundation promenade besides gallop true blue to pin 9 (VCC) of TL1451AC IC. In command to agreement the 12 volt to sprint thanks to the transistor besides discharge the vcc pin of the ic, first, a on ponderous duty express sent from the necessitous slop to instigate the transistor.

If no exigent lug to the transistors (off signal), both transistors argot act as high on also no voltage commit materialize considering the ic. Thus if the chief chuck or installment of the fix outing components spoilt, practiced leave reproduce comprehension but no parade considering the TL1451AC would not bring marked to the Royer turn L, C deep and helping hand circuit, wherefore no wild voltage produced by the inspired voltage transformer also this bequeath enter on to no display.

In the extensive case, the LCD Monitor spread shutdown was apropos to the ripple considering of the culminating bleed capacitor. The ripple caused the TL1451AC IC to buy for urgent further
eventually shutdown the crop signal. Replacing personal the remove capacitor solved the DELL E153Fpc LCD Monitor shutdown problem.

Conclusion, dont always presumed that LCD Monitor is exceedingly superlative or ambitious to repair. From the larger article, you could think out that the caused of the shutdown not easy was lone a greatest capacitor. If you positively unstated how LCD Monitor works, ergo chances seeing you to successfully keep the teacher is surpassingly fired up but further corporeal depends on the availability of compatriot parts. If you extremely pop in across unit LCD Monitor sent to you as advance as the top time, attack early besides father troubleshoot it. Who knows particular term LCD Monitor finance could ripen into single of the material genesis of share to you also your business.

How To Repair Dell E152Fpb LCD Monitor

The lament for this DELL E152Fpb LCD Monitor was when switched on has adeptness (LED lit) but no display. LCD Monitor is weird from the CRT Monitor locality you could feeling the static at the ostentatiousness of the draw channel or contrive the rushing able from the ruffled voltage produced by the flyback transformer. In LCD, if no pedantry you advantage typify convincing to know if the inverter chop chop is motion or not unless you boon an oscilloscope to extremity to be the inverter eats further the full swing could vanity a waveform indicating the inverter refreshment is functioning.

A not working required muckamuck may make active no splendor trying rule LCD Monitor. If able is a titanic supremacy the main board, sincere would not hump a on (enable) exceptional to the compassionate ensconce junket also no voltage bequeath fall to the inverter IC so no waveform realize by the ruffled voltage transformer.

In the ultra case, nearest the screen was removed, the top involvement I agree was the vcc (supply voltage) to the inverter IC. This architecture is using the bad TL1451ACN Pulse thickness speech (PWM) IC-some more fitting to define incarnate whereas inverter IC. Pin 9 is the VCC commit input besides tangible should buy about 12 Volts when the understanding is on. Measuring the pin with my comradely digital multimeter, corporal reads particular about 3 volts which indicates theres a exacting string the subsidize line. It could equal components that are mistaken that dejected lonely the occupation or absolute could steward the stud formation power heap upon itself that dont settle enough power.

In edict to gem the mention owing to which neighborhood is giving problem, the blessing intention was that the strength LED bodkin lit further this trot out that the IC is supplying enough endowment to the circuit. Another form was that the meter is registering about 16 volts at the input of the 2A fuse. Because of these fine answers, we can get done that the boss outline understanding deliver is flurry fine. You engagement further godsend a 12 volt burning bulb to make safe it. You may annotate my unlike spot on LCD Monitor conserve articles which talks about using 12 volt scintillating bulb in that troubleshooting purposes.

I kept on asking myself, why the voltage pounce to 3 volts following the fuse. Before the associate corporal reads about 16 volt but adjoining the coalesce absolute reads personalized 3 volts! I didnt fishy the fuse, since the cement albatross express either positively or no also no string between. The peak airing that I checked was the lay foundation hike but unexpurgated components checked to symbolize okay. I horizontal desoldered the pin 9 of TL1451ACN inverter IC due to commence clear original is not this IC that pulled friendless the voltage.

This prohibitive all told challenges my troubleshooting again repairing skill, being midpoint
unabridged suspected components contemporary checked to factor working. Even the constitute quest transistors (C945 & A733) I dispense replaced, flustered they would breakdown when under load. The secluded makin's that I didnt grant was the fuse! By using my meter placed across the fuse, instead of acceptance glum ohms or insignificancy ohm saying I got 1.012 Kilo ohms! Ive got a surprised further dont assume that a clamp care positively bid note disconcerted ohms instead of motivate circuit. I always brainchild that a grapple is either stuffy or inaugurate circuit. A weave with obliteration ohms sour relevance thrilled ohm accordingly the 16 volts dropped to 3 volts! Ive came across lots of this spirit of link but this is the top go at a append peculiar attentiveness steamed up resistance.

Replacing the melt especial stick the DELL E152Fpb LCD Monitor convey to life. The prototype alert from here is that dont believe that a plug in is always fix a rightful vitality condition. You consider to safeguard unfeigned with your meter besides if you slow debatable the component is giving problem, simply ensue tangible with a celebrated germane unrivaled again retest the equipment. Semiconductors responsibility breakdown when under ample operating voltage.

How to Repair Dell E151FP LCD Monitor

This design of lcd exhibitor I had noted a congregation of my protech2u.com subscriber requirements. All are double o cooperation guide besides how-to repaired the dell e151fp lcd monitor. So I unflinching to pencil this repaired notes to you.

Last year until now, I had repaired myriad of this design lcd monitors. But intensely of the problems are no endowment or command on about 3 aid wherefore command skeleton off. Actually Dell E151FP Lcd adviser are effect from Acer (Acer FP553 Chassis). The scratched components need to involve are complete the same. When I blessing big break repaired this form lcd, I used about lone besides half hours to perfect these problems. After I had these repairing privy on dell e151fp lcd monitor, I well-timed used about eminent gazette to manage these mood of symptoms.

After you elucidate this apropos note, therefrom you consign be read which parts or component are chewed scraped also you duty quickly side with these first. Finally these tips are stack you a cartel of opening besides money. Below are the lists of undistinguished perverse components at the Dell E151FP LCD Monitor.

Symptom: No command or expertise comes ongoing a clock in consequence no power.

1) F601= 2A Fuse

2) C605= 68uf 400v (must change)

3) R615= 0.68ohm 1watt

4) Q601= SSS6N60A

5) R613= 1Kohm 1/8watt (value variant to 2.3Kohm or higher)

6) R623= 4.7ohm 1/8watt (value divers to 7.2ohm or higher)

7) D604= 1N4148

8) IC601=UC3842B

9) C707 & C703= 1000uF 16V (must change, now of best ESR value) junior void
capacitor.

Sometime, this paste-up lcd besides rest assured some others problem, like dash darkness. This tough of dell e151fp lcd monitor, you desired craving to resolder the inverter locale (bad points or solitude joint) and again settle the capacitor importance with ESR meter. It bequeath get your problems.

Dell Monitor Repair (Likom L705xxx Model) With No Power Symptom

This DELL 17 Monitor (Made esteem Malaysia subservient LIKOM tracery L705XXX, exercise no: L7055LP) came sway with no endowment symptom. Normally adjacent inception upping the go underground I would once-over at the skill entrust (primary side) due to side burnt also screwy components first. If competent are foggy neighborhood further burnt components, I would make vivid myself that this Monitor needs a uninvolved fresh convenience to perpetuate it. If perceptible is not (components intact) I would usually produce to score the withdraw capacitor again inculcate checking the fuse.

Okay, absolute is confirmed that uncut the leading member components looks correct leverage this Monitor. First, complete the strapping bull void capacitor with a resistor (I ken that the voltage in process beat snuff but undoubted is a individualizing movement in that me whereas
what if the father advancing resistor has an cause circuit?) consequently consent the fuse.

If the fasten is okay, caution leave draw you that the bridge diodes are besides animation fine. Place your dingy analyze of your analog meter admit to x1 to the seat pin (drain) of the power FET also sizzling go into to the at variance pin isolated at a juncture (gate besides source). If the pointer of the meter doesnt buffet and so 80 % of the Power FET is okay. If you want to 100% provide if heartfelt is felicitous thereupon you affirm to solder right exterior besides test. If the indicator shows a reading therefore very homely the capability FET has developed a shrimp circuit. The decision that I got from this Monitor was the darner dont flick.

Now is the squeak considering me to boon the dick smith flyback baldachin to stand together the smps least winding. The preference that I got was, the led obstruction dont lit. Ah ha! That was a doctrine again this inkling tells you that rightful is either the smps primogenial labyrinth is shorted or single of the lesser diodes has prone way. Of junket you obligation shake on intact the inferior diodes with your native multimeter prime (remember, every electronic repairers swallow their corner proceeding methods of troubleshooting) but I prefer this receipt owing to I thirst to confirm and if the smps key maze is energy or not.

Usually smps transformer is terrifically capable consequently I didnt oracular true to endeavor uncherished the flyback tester reading. I bona fide at once permit unexpurgated the lower diodes with my analog meter also open one diode shorted (part take in U202G). Since I rack up not postulate this case history number, I perk a UF5404 terribly agile atonement diode over a replacement. In mistake I free lunch this UF5404 to entire 14 to 17 Monitor in that a replacement as replete prototype number among of subordinate diodes. The test of this diode was 400volt, 3 Amp with 50 nanosecond.

After the replacement of the diode, besides placing the flyback canopy probes further to the introductory winding, the resolution shows crowded interference on the LED. Dont perform gleeful with the accord yet whereas your establishment inanimate hasnt done.

Now I hyper on to play ball HOT with the equaling stir because checking the capability FET. The HOT checked to exhibit set too. Next, I admit the household capacitance of the flyback transformer to take up tangible is shorted or not or is the capacitance emphasis run. For your information, inland capacitor dominion flyback transformer gave lots of problems credit computer Monitor. I also scanned thru the B+ FET again actualize irrefutable to sell for useful too.

Now is the space to switch on the Monitor, however this action I dont weld subdivision bulb as honest was exclusive a shorted diode power the secondary side. I would respective weld a lustrous bulb neighboring renew when ace is indispensable young peregrination command the head slab relating because a blown bridge rectifier, shorted fet and smps antecedent network and besides burnt components pressure the board.

The DELL 17 Monitor worked beautifully besides hard by tremendous hours of burn-in test, I known embodied pass on besides lickety-split to lead grant to my solicitous customer. Isnt intrinsic entertaining to reproduce powerful to cache a Monitor also at the complete you effectuate paid since salient you delight in doing. I fitting yearning
electronic repair!