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Re: IQ SMART TV 22" weird problem
the 3.3v regulator is good. looks like the others get their voltage when the ps comes up.
if you have an esr meter, i would check all of the caps on the main board.
if they are ok, you might be looking at an eprom failure.WHY CAN'T PHILIPS USE PHILLIPS HEAD SCREWS?Comment
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Re: IQ SMART TV 22" weird problem
I don't have esr meter. Can I check it whith some other way? I have a meter that you put different componenet and tells you what it is (resistor,capacitor, diode etc) which measures the capacitors but I don't now if the values are good (I only understand uF , it gives me some readings like esr but I dont know the "good"values)
I had changed 3-4 capacitors but I didn't see any change in the behaviour.
When the TV came it has the thermal fuse blewed and I changed that.Comment
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Re: IQ SMART TV 22" weird problem
capacitance will only give you half the answers as to if the caps are good or not.
you can download an esr chart easy enough.
have you jumped the ps on with a resistor to (470 to 1k) see if the backlights and ps are all working properly? disconnect main for this.WHY CAN'T PHILIPS USE PHILLIPS HEAD SCREWS?Comment
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Re: IQ SMART TV 22" weird problem
This TV has an always on power supply, the ON/OFF pin that you measured 0V is the Backlight ON/OFF control pin and right now the main board is not sending the ON command to turn on the backlights.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809Comment
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Re: IQ SMART TV 22" weird problem
The TV is led not lcd so it has no backlightComment
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Re: IQ SMART TV 22" weird problem
bud, should this ps power the backlights as soon as the main is disconnected?
pull up resistors on the ps.
just wanted to make sure there was not multiple issues first.WHY CAN'T PHILIPS USE PHILLIPS HEAD SCREWS?Comment
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Re: IQ SMART TV 22" weird problem
It probably does not have pull-up resistor for self test. Since the standby power supply is 12V instead of 5V, you will use 2K resistor between 12v and ON/OFF, it also may require another 2K resistor between ADJ and 12V.
"The TV is led not lcd so it has no backlight" it uses LEDs to create the backlit or edge lit (more likely) for the light source.Last edited by budm; 04-14-2017, 08:52 AM.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809Comment
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Re: IQ SMART TV 22" weird problem
disconnect the cable that goes to the main board from the ps.
use a 2k resistor to jump from 12v to on/off.
either place it into the connector holes that are now available at the end of the cable that you just disconnected, or wedge it into the cable connector that is still attached to the ps.
if this does not turn on the backlights when power is applied (no buttons need to be pressed), then add another resistor between 12v and adj, then apply power again and you should see backlights but no picture.
this will let you know that the ps, backlights and panel are ok (visually).
after this, you can return to the main board that has your issue, whether it can be fixed or replaced, but at least you will know that you should have no other issues at this point.WHY CAN'T PHILIPS USE PHILLIPS HEAD SCREWS?Comment
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Re: IQ SMART TV 22" weird problem
so ps and screen are good. the sound may always be there and your only noticing it since you have the back off and your next to the ps. it is hard to tell for sure from a keyboard.
on the main, i would check all of the caps, then if that gets you no where, i would try to do a reflow of the main processor that is under the heat sink. if it is a bga chip, they do tend to fail with broken solder connections. outside of that, you could be looking at the eeprom chip.
main boards are a bit annoying and you could be up for a replacement board at the end of the day.WHY CAN'T PHILIPS USE PHILLIPS HEAD SCREWS?Comment
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Re: IQ SMART TV 22" weird problem
The sound is always there when the TV cannot turn on. If I turn it on the sound disappears. The caps are all good, at least with eye inspection.
I did a reflow on the chip (it is bga) but still the same. I only have the red standby led but cannot power on the TV.Comment
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Re: IQ SMART TV 22" weird problem
caps can fail without any visual signs.
you can try and freeze the eeprom chip, it may boot when frozen.WHY CAN'T PHILIPS USE PHILLIPS HEAD SCREWS?Comment
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Re: IQ SMART TV 22" weird problem
I don't have freeze spray but I have compressed air wich freeze it but it doesnt turn on. Can I try and inject voltage to a regulator to see if it turns on?Comment
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Re: IQ SMART TV 22" weird problem
unfortunately it looks like you need another main board.
unless someone else can suggest something else that you can try.WHY CAN'T PHILIPS USE PHILLIPS HEAD SCREWS?Comment
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Re: IQ SMART TV 22" weird problem
I was trying to turn it on those days and I couldn't . I left it with power for 3-4 hours and then it turned on.
I have 5 V on pins on/off and adj
and in all regulators 3.3V in middle pin and 5V in right pin.
Also the weird noise dissapeared as soon as the TV turned on.
It is as something is not charging correct and it has to get a lot of voltage before it can turn on.Comment
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Re: IQ SMART TV 22" weird problem
You can try heating/cooling different areas of mainboard to see if it makes a difference.I assume no responsibility for any stupid suggestions I might post.Comment
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Hi, this is my personal laptop, which the original board (lets call it Board A) blew up PU8700 (TPS51486), making a hole on the board, i had left the laptop at my desk one day with the battery fully charged and didn't touch it for a week, but when i tried to turn it on it didn't
Thought the battery was dead, so i plugged in the charger then tried to power on, the power LED blinked once, charged LED still orange, unplugged the charger, plugged in again and I noticed the "magic smoke" smell, so i unplugged the charger, removed the back cover and saw the blown IC (the "magic... -
Hi there!
I have a Sony Bravia KDL-40Z4500 which shows a colored vertical stripes pattern when turning on, with a central black shadow that slowly dissipates within the first 10 seconds.
Photo of the situation after the black shadow dissipates:
After this behavior the red LED will blink 9 times, then pause for a bit, and blink again 9 times, in a loop.
I checked the manual (available here) and this corresponds to "HFR error", quoting from the manual:
> This indicates HFR Communication error. [ HFR Communication... -
Vizio e601i-A3 - Has Sound and Display, But No Backlight - Bad Power Supply Board or Bad LED Bulbs ?I was given this TV from my great uncle. He said it just wouldn't turn on one day out of nowhere, replaced the TV, and gave it to me to possibly fix and use for myself.
Upon bringing it home and plugging it up, it showed a standby light.
I powered it on and without a flashlight, the display showed the "V" but the lighting is very dim, but visible.
The screen seems to blackout and stay black, but with a flashlight I can see the display.
With my Playstation 4 connected via HDMI, and running a game I can hear sound.
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Hello, I came here after finding some similar questions asked on other monitors and hope someone here can help me get an ancient Viewsonic VP230mp (23" 4:3 LCD) back to working condition.
First a little background, I have a background in computer and electrical engineering, and I'm smart enough to know I know nothing about LCD displays and how they work. For this topic I'm as green as they come.
When the display is turned on the viewsonic logo displays in the uppper left for 2 seconds then the screen goes black, the power LED is green (on) and when a computer is connected...
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