Tyris Monitors turn on then shut off within 1 second

[indyracer]

I have 2 monitors (same make and model) that started having the same problem in the same week. When you plug them in, they turn on for about 1 second and turn back off. They will continue to do that until you hit the power button or unplug the power cable. I took them both apart and the same capacitor was split down the sides. I have included a picture with the part circled that I replaced. After replacing these parts, both monitors still have the same behavior. What else should I be looking at? I can get more pictures if needed.

Thanks for the help..

Tony

Photo

[PlainBill]

Re: Tyris Monitors turn on then shut off within 1 second

I have 2 monitors (same make and model) that started having the same problem in the same week. When you plug them in, they turn on for about 1 second and turn back off. They will continue to do that until you hit the power button or unplug the power cable. I took them both apart and the same capacitor was split down the sides. I have included a picture with the part circled that I replaced. After replacing these parts, both monitors still have the same behavior. What else should I be looking at? I can get more pictures if needed.

Thanks for the help..

Tony

Thanks for the picture, at least one more will likely be required. It makes it easier if you attach pictures by scrolling down to 'Additional Options' and use the 'Manage Attachments' button.

Your description of the problem is ambiguous, so let's see if we are on the same page her. I interpret it this way. You hook the monitor up to a working computer and turn it on. The power LED and screen come on and the monitor displays the desktop for a second, then the screen and power button go dark. Some time later (how long?) they repeat this process. Is that correct? If so, it points to a specific capacitor in the power supply, not the one you replaced. I have never seen or heard of that behavior (but I haven't seen ever possible monitor fault). But it wouldn't be the first time a component had an obvious flaw, but still worked properly.

What I have seen goes like this: The monitor is hooked to a working computer and plugged in. The power button is pressed and for a second or two you have the desktop displayed. The screen goes black, but the power led stays on. If you hit the power button once, it goes black. Hit it again and the desktop is displayed for a second or two. In this case, the failed capacitor likely caused another a shorted transistor.

To make more progress, please attach a good picture of the bottom side of the circuit board. And of course, clarify the symptoms.

PlainBill

[indyracer]

Re: Tyris Monitors turn on then shut off within 1 second

Thanks for the quick reply.

You are correct. When you power on the monitor, the screen and green power light comes one for about 1 second then go out. About 2 or 3 seconds later they come back on and the process just repeats until you unplug the monitor. I have pressed the power button during this process and the monitor stays off, but as soon as I turn it back on it just continues with the on off cycle.

I have attached a photo of the bottom of the board.

Thanks so much for your help.

Tony

[PlainBill]

Re: Tyris Monitors turn on then shut off within 1 second

Thanks for the quick reply.

You are correct. When you power on the monitor, the screen and green power light comes one for about 1 second then go out. About 2 or 3 seconds later they come back on and the process just repeats until you unplug the monitor. I have pressed the power button during this process and the monitor stays off, but as soon as I turn it back on it just continues with the on off cycle.

I have attached a photo of the bottom of the board.

Thanks so much for your help.

Tony

This is a rather unusual monitor power supply. I'm used to seeing 5V and 12V outputs; this one has only 12V out. The symptoms indicate the power supply is overloading, shutting down, then restarting. The fact that it shuts down from the power button would indicate the problem is in the inverter section.

I've marked up the pictures. On the picture of the bottom, I've circled two transistors in bright red. These are associated with the capacitor you replaced. Check them for shorts. The pair of transistors circled in dark red are on the other side; they should have the same readings as the first pair.

I've also circled an IC in Blue, and another in black. What are the part numbers for those ICs? Also, what are the part numbers for the transistors?

If the transistors check out, I've circled a single capacitor in bright red on the top picture. That could cause the problems you are seeing, but it's a long shot. One test you could try is to hit the power button while it is on, ending the cycle, then measure the voltages on the output connector (12V to Gnd). If that is stable, it is certainly an inverter issue.

Also, what are the numbers on the original and replacement caps on those you replaced?

PlainBill

[indyracer]

Re: Tyris Monitors turn on then shut off within 1 second

This is a rather unusual monitor power supply. I'm used to seeing 5V and 12V outputs; this one has only 12V out. The symptoms indicate the power supply is overloading, shutting down, then restarting. The fact that it shuts down from the power button would indicate the problem is in the inverter section.

I've marked up the pictures. On the picture of the bottom, I've circled two transistors in bright red. These are associated with the capacitor you replaced. Check them for shorts. The pair of transistors circled in dark red are on the other side; they should have the same readings as the first pair.

I've also circled an IC in Blue, and another in black. What are the part numbers for those ICs? Also, what are the part numbers for the transistors?

If the transistors check out, I've circled a single capacitor in bright red on the top picture. That could cause the problems you are seeing, but it's a long shot. One test you could try is to hit the power button while it is on, ending the cycle, then measure the voltages on the output connector (12V to Gnd). If that is stable, it is certainly an inverter issue.

Also, what are the numbers on the original and replacement caps on those you replaced?

PlainBill

I will check for shorts tomorrow.

The part number on the transistors is C5706. I will have to get the number off the ICs tomorrow.

Part number on original capacitor is F .33J PMD 250V
Part number on replacement capacitor is F334K K 250MPP1.
I sent a picture of the original to Mouser and the replacement is what they gave me as a replacement.

I will get the other information in the morning.

Thanks so much,
Tony

[PlainBill]

Re: Tyris Monitors turn on then shut off within 1 second

I will check for shorts tomorrow.

The part number on the transistors is C5706. I will have to get the number off the ICs tomorrow.

Part number on original capacitor is F .33J PMD 250V
Part number on replacement capacitor is F334K K 250MPP1.
I sent a picture of the original to Mouser and the replacement is what they gave me as a replacement.

I will get the other information in the morning.

Thanks so much,
Tony

This is essentially the same circuit as is used on countless Dell monitors, and the same fixes apply. Resolder all transformer pins, replace the shorted transistors.

PlainBill

[ianmax]

Re: Tyris Monitors turn on then shut off within 1 second

This is essentially the same circuit as is used on countless Dell monitors, and the same fixes apply. Resolder all transformer pins, replace the shorted transistors.

PlainBill

i have same problem too, the power board an inverter same with haier monitor F17 series. is short bye the 334j capasitor.....test by me

[budm]

Re: Tyris Monitors turn on then shut off within 1 second

The blue and the brown caps are part of the Royer tunning Oscillator circuits, if they are bad or have big change in value, it will cause the transistor blow out due shorted caps or it is running at the wring frequency so they will draw too much current. You can see some of those bad caps here:
http://s807.photobucket.com/albums/y...%20capacitors/

[ianmax]

Re: Tyris Monitors turn on then shut off within 1 second

hi all. i have another monitor model this is viewsonic VE710-5 this problem same with this forum after i turn it on screen come and shut off after -+ 2 second , i have change C5706 4 pcs ,and .33j 250v caps. but still the same with the problem....any one help....me


Thanks V'Much

[selldoor]

Re: Tyris Monitors turn on then shut off within 1 second

@ianmax - Hi Please can you confirm that you have power supply DCAC40A4

We can help a lot more if you please post good clear pictures of the whole chassis, and then pictures of each board, front and back and close up of connectors, (max resolution 2000x2000 and 2MB) using the manage attachments button, which is found by clicking "go advanced" under quick reply.

Please do not post inline and offsite as they slow down the loading of pages.

Examples of what is needed
https://www.badcaps.net/forum/attach...1&d=1290283049

https://www.badcaps.net/forum/attach...7&d=1280167246

It will be useful if you can say a bit about yourself - skills tools etc. Please also update your profile with country and voltage.

What make/series replacement caps did you use?.

Whilst you have not given much info to go on you should probably read this Guide by retiredcaps: https://www.badcaps.net/forum/showthread.php?t=10419
Start at post 19.

[budm]

Re: Tyris Monitors turn on then shut off within 1 second

Ianmax, it may be good idea to start the new thread with Viewsonic VE710 heading so people that are looking for Viewsonic thread will be looking at the right thread, just a suggestion.