Question about Projection Televisions

1 Answer

Power outage due to power surge, possible fuse problem, tv will no longer turn on

Posted by on

1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    MVP:

    An expert that gotĀ 5 achievements.

    Governor:

    An expert whose answer gotĀ voted for 20 times.

    Hot-Shot:

    An expert who has answered 20 questions.

  • Expert
  • 54 Answers

You have a power supply issue on the main board of your set. This is not an easy fix for a home owner, Your best bet is to call a service shop and get a price quote. Tearing into tv's is very dangerous! High voltage is present even when unplugged! Good luck!

Posted on Aug 19, 2008

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

I have a RCA HD50LPW175 TV and it keeps blowing the 6-Amp fuse125v. Why?


Either you have a dead short or you used the wrong fuse--not all 6a fuses are the same---buy a cheap generic one from Radio shack etc and it can blow for no reason.

If not the wrong fuse---the fuse you are talking about should be where power enters the set--means a short on primary side of set's power supply---somewhere between power cord and input side----possible the bridge rectifier is shorted.

l have usually seen this when there was a power outage or a surge on the incoming power line.

May 28, 2012 | RCA Projection Televisions

1 Answer

Our electricity went out for a few minutes, and since then the TV will not turn on. The green light is flashing. We tried resetting it by pushing a pen point into the reset hole, but it does nothing. ...


Your power outage may have been caused by a nearby lightning strike, or any number of
1000 different reasons that cause power surges, brown-outs, voltage spikes, inductive loading,
and/or utility pole breaker trips and resets (this accounts for your power loss (a pole breaker trip),
followed by restoration of power (the pole breaker automatically reset) - even plain old high electrical demand causing an overload due to air conditioning demands caused by hot weather.
When the pole breaker reset, your TV caught a power surge.
Whenever a power outage occurs, quickly power off (or better, unplug) any/all computers, TVs,
etc. that are not protected by surge-protection.
As an electrician, when someone loses an item of electronics concommitant to an electrical
anomaly, its almost
always traceable to a nearby lightning strike (or the power company provided equivalent), accompanied by inadequate surge protection for
the VCR/TV/Computer/Stereo/uninsured valuable electronic item/XBOX 360/Nintendo Wii.
Surge protection can
be provided by the consumer at the power strip (a good one with builtin MOV protection and a
warranty costs $20, whereas a zero-protection 4-outlet or 6-outlet power strip will cost $4-$5).
Your electrician can provide whole-house surge protection where a whole-house MOV-based (metal oxide varistor) surge protector, or per-circuit protection can be installed with
a GFCI breaker (or better, an AFCI breaker) can be installed.
GFCI = ground fault circuit interruptor
AFCI = Arc fault circuit interruptor
Lightning protection is especially important in Florida, which is the "lightning capital of the world."
I've never found a good solution to lightning-fried electronics (random power supply components are destroyed and/or fuse blown), other than renters insurance or homeowners insurance.

Your only real hope for an economical fix is to look for a blown fuse, and replace it.

If desperate to attempt a fix on your own, you could try replacing the entire TV power supply as a module, but even this provides
no guarantee of a fix - lightning damage can extend beyond the power supply.
When traveling, I will always unplug everything before I leave (except the security system),
and also turn off the breakers to unneeded house circuits (which kills the wall switches that
control interior lighting - forcing a burglar to use their flashlight instead of interior lighting)
which is the least convenient lightning protection, but highly effective, and cheap (free).

Sep 05, 2011 | Mitsubishi WS-55511 55" Rear Projection...

1 Answer

After a 5 second power outage, the tv will not turn on.


Possible that the power while returning had a surge- this happens as the power needs to load up to stabilize . So it is always ideal to switch off power to all electronics devices when the power fails as if you are residing in the vicinity of the transformer then the surge will be high.
This will effect the power supply section which is a SMPS unit. Possible fuse or a driver would have failed.
Please check the link below for help:


http://www.fixya.com/support/r5826301-working_switch_mode_power_supplies

Feb 15, 2011 | RCA P52926 52" Rear Projection Television

1 Answer

Tv wont turn on?


Hello,
first you have to open the back cover of the television to check for blown fuses.

A blown fuse is a very common type of fault due to poor design very often triggered by power surges due to outages. However, the most likely parts to short are easily tested, usually in-circuit, with an ohmmeter and then easily removed to confirm.

Note that it *may be* useful to replace a fuse the *first* time it blows (though it would be better to do some basic checks for shorted components first as there is a small chance that having a fuse blow the second time could result in additional damage which would further complicate the troubleshooting process). However, if the new one blows, there is a real problem and the only use in feeding the TV fuses will be to keep the fuse manufacturer in business!

Sometimes, a fuse will just die of old age or be zapped by a power surge that caused no damage to the rest of the TV. However, it must be an EXACT replacement (including slo-blow if that is what was there originally). Else, there could be safety issues (e.g., fire hazard or equipment damage from too large a current rating) or you could be chasing a non-existent problem (e.g., if the new fuse is not slo-blow and is blown by the degauss circuit inrush current but nothing is actually wrong).

If the fuse really blows absolutely instantly with no indication that the circuits are functioning (no high pitched horizontal deflection whine (if your dog hides under the couch whenever the TV is turned on, deflection is probably working).) then this points to a short somewhere quite near the AC power input. The most common places would be:

Degauss Posistor - very likely.
Horizontal output transistor.
Power supply regulator if there is one.
Power supply chopper (switchmode) transistor if there is one.
Diode(s) in main bridge
Main filter capacitor(s).

You should be able to eliminate these one by one.



Test the rectifiers individually or remove and retest the resistance.


If these test good, use an ohmmeter with the set unplugged to measure the horizontal output transistor. Even better to remove it and measure it.

C-E should be high in at least one direction.
B-E may be high or around 50 ohms but should not be near 0.

If any readings are under 5 ohms, the transistor is bad. The parts sources listed at the end of this document will have suitable replacements.

If the HOT tests bad, try powering the set first with your light bulb and if it just flashes once when the capacitor is charging, then put a fuse in and try it. The fuse should not blow with the transistor removed.

Of course, not much else will work either.

If it tests good, power the set without the transistor and see what happens. If the fuse does not blow, then with the good transistor (assuming it is not failing under load), it would mean that there is some problem with the driving circuits possibly or with the feedback from the voltages derived from the horizontal not regulating properly.

Look inside the TV and see if you can locate any other large power transistors in metal (TO3) cans or plastic (TOP3) cases. There may be a separate transistor that does the low voltage regulation or a separate regulator IC. Some TVs have a switchmode power supply that runs off a different transistor than the HOT. There is a chance that one of these may be bad. If it is a simple transistor, the same ohmmeter check should be performed.

If none of this proves fruitful, it may be time to try to locate a schematic.

A blown fuse is a very common type of fault due to poor design very often triggered by power surges due to outages or lightning storms. However, the most likely parts to short are easily tested, usually in-circuit, with an ohmmeter and then easily removed to confirm.
But if otherwise your power supply board is dead, It can be dead at anytimes.Tries websites Shopjimmy.com,Ebay.com to buy a refurbish power supply board for the replacement.
Hope this helps....

.

Jun 05, 2010 | Zenith R57W46 57" Rear Projection...

1 Answer

Just bought a used Toshiba TAC 9530. Owner said it worked. I plugged it in and have no power, no indicator light, nothing. Can anyone help or have I paid for a very large paper weight?


Hello,

A blown fuse is a very common type of fault due to poor design very often triggered by power surges due to outages or lightning storms. However, the most likely parts to short are easily tested, usually in-circuit, with an ohmmeter and then easily removed to confirm.

Note that it *may be* useful to replace a fuse the *first* time it blows (though it would be better to do some basic checks for shorted components first as there is a small chance that having a fuse blow the second time could result in additional damage which would further complicate the troubleshooting process). However, if the new one blows, there is a real problem and the only use in feeding the TV fuses will be to keep the fuse manufacturer in business!

Sometimes, a fuse will just die of old age or be zapped by a power surge that caused no damage to the rest of the TV. However, it must be an EXACT replacement (including slo-blow if that is what was there originally). Else, there could be safety issues (e.g., fire hazard or equipment damage from too large a current rating) or you could be chasing a non-existent problem (e.g., if the new fuse is not slo-blow and is blown by the degauss circuit inrush current but nothing is actually wrong).

If the fuse really blows absolutely instantly with no indication that the circuits are function whenever the TV is turned on.

May 30, 2010 | Projection Televisions

2 Answers

No picture (black screen); making popping/crackling sound


there is a possibility that the semiconductor in power supply side damaged due to electrical surge. more likely the STR IC of Diodes.

Jun 01, 2009 | RCA P61960 61" Rear Projection Television

1 Answer

I had a power outage and now the tv will not power on. This is for a 55" Mitsubishi WS-55511. no green blinking lights.


Hi,

You may have a blown fuse. Unplug the TV and remove the back. Look for a small fuse near where the power cord goes in.
If it is blown that may be the problem.
Use a magnifying glass to read the AMP rating.
replace the fuse and plug it in. If the fuse blows again you need expert repair services.

If the fuse doesn't blow then try to turn it on.
If it turns on then check the operation of the TV.

If the fuse blows again or the TV won't work correctly then you need expert repair service to fix your TV.

You may be able to have your household insurance pay if it is damaged by lightening or a power surge.

Lee

May 02, 2009 | Mitsubishi WS-55511 55" Rear Projection...

2 Answers

TV wont turn on


have you checked the fuses inside the set. The power outage could have surged just enough to blow the fuse. Dont forget to unplug it when you check the fuse.

Jan 21, 2008 | RCA P52937 52" Rear Projection Television

1 Answer

TV won't turn on after power outage


LOT OF TIME WHEN YOU LEAVE IT OFF FOR THE NIGHT DISCONNECT POWER CORD DEFECTIVE SURGE PROTECTOR IS NOT GOOD FORE EVER PLUG TV IN THE WALL WITOUT THE SURGE PROTECTOR IF IT GOOD CHANGE THE SURGE PROTECTOR FOR NEW ONE CHEERS

Jan 17, 2008 | Hitachi 60UX54B/55K 60" Rear Projection...

Not finding what you are looking for?
Projection Televisions Logo

Related Topics:

67 people viewed this question

Ask a Question

Usually answered in minutes!

Top Projection Televisions Experts

Jaime Hernandez

Level 3 Expert

2267 Answers

matt martin
matt martin

Level 3 Expert

1191 Answers

yadayada
yadayada

Level 3 Expert

60867 Answers

Are you a Projection Television Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...