Acer 1714 flashing PLED and back lamps

[alexanna]

Acer 1714 17” monitor with external power supply.
This monitor is exhibiting a sec. to black issue, showing the Acer logo with the PLED flashing and the back lamps at the same rate.
I have installed 4 good ccfls once from a 17” panel and then from a 19” panel and the flashing of the PLED stops and the ccfls work as they should.
I have dissembled the panel thinking I had bad ccfls, but I am seeing something I have not seen before,
The ccfl tubes are horseshoe. And of course I don't have any bulbs like these.
All of the ccfls will light up when I test them with a ccfl tester except only just a liitle more than half of the ccfl light up.
I have had very good luck using known good bulbs to identify bad ccfls but I am unsure on this one. Short of finding exact size and length is there anything I could do to diagnose this?
Al.

[shovenose]

Re: Acer 1714 flashing PLED and back lamps

that half-working ccfl is causing the monitor to shut off because it probably has out of spec resistance or something.

[alexanna]

Re: Acer 1714 flashing PLED and back lamps

I may have answered my own question, I found a different power supply of similar voltage and amperage, and it looks like I had a defective power supply. The power supply is rated at 19v 3.16a.The voltage tested good at 19v but testing it with an automotive 1157 bulb only the small filament would light drawing 678Ma. The larger filament would flash dimly, when tested with the good power supply the larger filament would light brightly and it was just drawing just over 2.17A.
So I guess the larger horseshoe bulbs required more amperage to work correctly.
Al.