External monitor not working

Hi,

I just recently had problems with my external monitor not working. It was working just fine until today.

My mac can recognize the external monitor. The monitor shows up then 1 second later it goes to black. I'm using a vga connector.

I have a white mac book.

Any help?

Check the VGA adapter and cable. Sounds like one or both may be loose or defective.

I tested the mac adapter on another vga cable and it still shows up for 1 sec and then turns to black screen.

I also tested the external monitor on a pc and it does the same thing, shows up 1 sec then turns to black screen.

The monitor is still on because I can see the red light on the power button.

I don't know why this is happening but if the monitor is broken, it should not even turn on.

OK, it sounds like the monitor may be having problems. Rarely does a monitor go out, so I would suspect the connector on the monitor itself. Check the connector to see if any pins are bent or if it's loose. Also check the AC power plug and cord on the monitor since it could be losing power intermittently and causing it to go black.

I did some further research and my problem has happened many times. The root of the cause is hardware with the Samsung monitor. A capacitor is more than likely blown. I would have to open up the monitor to see.

Does anyone know where to purchase capacitors from? I have a samsung.

Realest99 said:

Does anyone know where to purchase capacitors from? I have a samsung.

Click to expand...

Radio Shack is your best bet for purchasing small parts such as capacitors and resistors. Otherwise going on line and looking for electronic suppliers is what you'll need to do. Also check out your local yellow pages for electronic parts stores.

chscag said:

Radio Shack is your best bet for purchasing small parts such as capacitors and resistors. Otherwise going on line and looking for electronic suppliers is what you'll need to do. Also check out your local yellow pages for electronic parts stores.

Click to expand...

Thanks for the suggestion.

I just took apart the monitor. All the capacitors on the supply/inverter board look fine. None are bulging or look disfigured from what I see. They are sam young. Should I just go ahead and replace all of them?

Capacitors are almost impossible to check while in circuit (soldered to the board) because of current paths. Shorted capacitors are not uncommon in power supplies but they'll usually cause a fuse or built in circuit protection to trip.

The blacking out of the monitor may not be from a defective capacitor. There are other power supply components that can cause the same thing to occur. What would be great is if you could find another power supply for the monitor and swap it out with the old one.

But I guess if you're good at soldering and un-soldering components and feel up to it, you could replace all the power supply capacitors. Electro caps are usually the ones that fail.

Samsung TVs I know from around 07 had problems with capacitors. Our family TV had this little board with capacitors replaced under warranty in our house. The TV would constantly turn on and shut off. Maybe the same type of problem?