Acer AL1916W Ab Monitor, DAC-19M008 - No Backlight, Recapped, Can see with Flashlight

[PlainBill]

Re: Acer AL1916W Ab Monitor, DAC-19M008 - No Backlight, Recapped, Can see with Flashl

Good pictures, and a good summary of what you have done. The only detail I would have added is the series of caps you used; we'll get back to that later if necessary.

In addition the Dgtech's suggestion, check F200 to see if it's good.

Carefully check the voltage at C200 with power on.

Check the voltage at the top two pins of the connector to the logic board. They are brightness and On/Off control of the inverter. Do this while the monitor is hooked to an active video source, and again while it is in standby.

Check for any light from the CCFLs by cycling the power button in a dark room, or watching from the back. Certain failures can result in a very brief flash of light (.1 seconds).

What is IC 200?

PlainBill

[Dgtech]

Re: Acer AL1916W Ab Monitor, DAC-19M008 - No Backlight, Recapped, Can see with Flashl

Check F102 also on the solder side of the board.

[Anonymous333]

Monitor: Acer AL1916W Ab
Inverter / Power Supply Board: DAC-19M008 BF Rev:01A
Manufactured: 8/2006

Status: Monitor works, but CCFL Bulbs don't come on at all. I can see the LCD display functioning properly with a flashlight held up to the screen.


Prior Symptoms: The monitor began to cease to come out of it's sleep mode correctly, in doing so the power button's amber LED light (sleep / screen save mode) would change to green when coming out of sleep mode, but the CCFL lamps wouldn't always come on unless I recycled the power by pressing the button off then back on again. Over time, this symptom began to occur more and more frequently along with me beginning to have to power cycle the monitor multiple times before the lamps would "kick start". When they were on, they were full power and worked fine until either the monitor went into sleep mode, or when I turned it off, and turned it on the next morning. (If I were to turn it off and turn it back on again, while it was still "warm", there was no problem, but if enough time went by ....no dice). Eventually, it took upwards of around 15 to 30 power cycles to get them to "click on", so I could use the monitor for the day, but one day they just quit coming on at all.

I have since found this forum, read all articles pertaining to monitors (Acer, Westinghouse, etc.) with similar boards and problems, and still can't figure out the best way of finding out the problem.


Repairs: Replaced all cylindrical (CapXon) caps, some of which were bulging, (minus replacing the large CE106 cap) with Nichicon, Mallory, & IC replacement caps.

Replaced both MOSFETS (IC101, IC202), one of which was shorted.

Replaced blown Fuse (F200)


So far this has not helped any, the LCD still works, and the bulbs still do not illuminate. This is where my problem deviates a bit from most others.


Additional Info: For testing I am armed with only a digital multimeter and hope. With any luck, I may be fortunate to have someone guide me to what is thought to be the best areas to check from here. There are many things I don't yet understand. One of which being whether the condition of one bulb causing the board not to read the correct voltage or amperage and as a result possibly not lighting them all. At the moment I have no way of testing the bulbs, but I don't imagine they all 4 went out at once as they all would come on at once after previous coaxing by power cycling. ...things of this nature.

For anyone willing to give this a shot, I can give you readings off the board at your request. I'd really love to get this monitor repaired so I can start another chain of hand-me-down upgrades for others as I have bought a new one since. Thanks.

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