People's standard of living is good, and families have eliminated their heavy headlights and replaced it with a fine atmosphere of lcd tv. Hae-shin is the first-line brand of the domestic electricity industry, which sells very well under the flag of lcd tv, which is mainly due to the quality of its products. However, one such or another problem arises when the best products are used for a long time, as is also the case for cilss. This sub-author focuses on a few examples of the maintenance of wist, which it is hoped will help maintain。
Type: tlm4237
Fragmentation: no sound at times
Review process:
As this malfunction occurs on an irregular basis - without a sounding of the map, it is first used to measure the voltage detection points of the power panels, e. G. +5v, +12v, +24v. When back-photo voltage +24v is measured, voltage instability occurs and is tested several times, sometimes with a start (screen) and sometimes without a start. The plug-in of the back-light source plate is removed to see if there is a problem with the load circuit and then the +24v end is measured, at which point the voltage remains unstable and the failure can be determined on the source plate。
It is normal to measure b+pfc voltage of about 380 v; it is stable and clearly abnormal to measure +24 v voltage. The #4 foot (starting the power foot) of the thick membrane integrated circuit ne003 (str-6769) is measured. The normal voltage should be 16-18v. In case of failure, the foot voltage between 10-16v becomes about 10v, and +24v is expressed as shaking. Last tested, the reason for the failure was the reduced capacity of the absorbing circuits, which caused instability in the +24v start-up, and the failure was eliminated after the replacement of the capacitation ce023 (6800p/2kv)。
Type: tf2919h
Fault phenomenon: irregular black screen
Review process: based on the failure phenomenon, integrated circuit n201 (tmpa8859-5) and high frequency head a101 (tdq-3h3-hs-1) have been inspected and replaced, the test engine has turned off the black background, the failure has a dim snowflake, there are intermittent sounds, and welding is suspected. Opens the shell, and when a malfunction occurs, it recovers by pressing the large plate, and looks like the large plate does have a weld in place, looking for a light, placing the circuit board everywhere, and not finding a weld or a broken plate, and there's a change in the right hand presses the large plate。
Quietly and carefully, there is an accompaniment for snowflakes that fail to work, and there is a problem of dark snowflakes that should be part of the middle discharge route, and the words of the accompaniment seem to indicate that the middle discharge route is normal. A careful examination revealed that when the negative end of the cap c811 was pressed, the snowflake on the screen became visible and the problem appeared to be here. Carefully, the leg of the positive polar component of c811 did not cross the circuit board at all, which should be a fake weld. In order to prove the problem, using the capacitor to cross c811, the television was back to normal, confirming my thinking. The capacitor was reprocessed and the television was restored。
The analysis of c811 is the tv-video signal to tc4053 (av/tv) to switch the condensed caps of an integrated block, which, if welded, should have a black screen failure rather than a dark snowflake. The analysis found that the c811 electric welds introduced interference signals。
3 type: tlm46v69p
Fault: three nothings, lights on
The process of overhauling is open, lights are lit, machines are first upgraded and failure continues. The shell measured the voltage at all points and found that the integrated circuit u5 (ams1117-3. 3) was abnormal at 1. 3 v, and the normal voltage was 3. 3 v. Measurement of input end voltage 5vstb is normal and failure is eliminated after the trial replacement of integrated circuit u5。
Analysis of this failure may be due to the abnormality of the voltage or to mass problems of the metaware itself。
The above three examples of the maintenance of the isl tv. Tlm4237, tf2919h and tlm46v69p, which are relatively high purchasing rates, are more representative in terms of examples of the failure and removal methods of cnts. In addition, the three types of failures described above are more common for lcd television, even if there are more than one type of lcd television, and it is believed that one can easily resolve one's own icd television failure by referring to minor maintenance methods。
