Question on simple monitor fix - Page 1
Forum section: electronics / beginners

author: Mike89
author_rank: Newbie
timestamp: March 26, 2014, 03:16:14 pm
content: Saw the vids on the simple monitor fix replacing bulging capacitors. Here is my problem. Monitor (Acer G235H) comes on for a second and then goes black. If I turn monitor off and on again I see the image again for a second and then black again. Same thing will happen as many times as I turn the monitor off and on. Monitor blue light stays on (as opposed to amber light when monitor goes to stand by) the whole time after powering up even when monitor goes black. Sounds like my monitor qualifies for the capacitor issue.Problem is I took the monitor apart and all the capacitors look fine, no bulging at all. Does this sound like bad capacitors are still causing my problem or is my problem something else? I'm a rookie so have no means of checking each capacitor (other than visually). Any help appreciated.

author: granz
author_rank: Regular Contributor
timestamp: March 26, 2014, 03:28:39 pm
content: You'll want an ESR meter to really check the capacitors.http://en.wikipedia.org/wiki/Equivalent_series_resistanceEdit: You can be almost certain they have gone bad if they are bulging/leaking, but it doesn't work the other way around--you can't be sure they are good if they look OK.You can find inexpensive ESR meters on eBay. They may not be very high quality, but would serve your purposes.

author: mariush
author_rank: Super Contributor
timestamp: March 26, 2014, 03:54:25 pm
content: Before investing in a esr meter, you'll want to investigate the CCFL tubes.This behavior you see is often caused by a poor contact between the wire and a ccfl tube, or a ccfl tube that's too old and drawing too much current.In both cases, the inverter tries to start the lamp pairs and it monitors the actual current consumption and whether the lamps actually run or not. If there's a poor contact at the end of a cclf tube, a pair of lamps won't start and then the inverter turns itself off.If one of the lamps is going bad due to age or some manufacturing problem, the lamp will pull more current from the inverter which can damage the transformers and inverter circuit, so the inverter IC kills the backlight.You'll have to open up the back panel and check the silicone ends of the ccfl tubes and the wires and if the cable is just loose, resolder it. If the ccfl tube is bad, you'll probably have to replace both tubes at same time (if not all four, if you don't want the other pair to go bad in a year or so) and they cost about 10$ each, plus shipping.See this gallery for examples of desoldered/broken wires :http://s807.photobucket.com/user/budm/media/Bad%20backlight%20lamp/DSC01525.jpg.html?sort=3&o=4And this gallery shows examples of bad ccfl tubes :http://s807.photobucket.com/user/budm/media/Bad%20backlight%20lamp/DSCF1700.jpg.html?sort=3&o=22

author: Yago
author_rank: Frequent Contributor
timestamp: March 26, 2014, 05:15:19 pm
content: They (lamp connections) can arc at the connection too I think?Seals can go if too much heat/time soldering on ht lead.

author: Shock
author_rank: Super Contributor
timestamp: March 26, 2014, 05:35:04 pm
content: That is a fairly new monitor isn't it. Is it still under warranty?

author: miguelvp
author_rank: Super Contributor
timestamp: March 26, 2014, 06:39:50 pm
content: Before poking around the ccfl circuitry be aware and beware that you are dealing with High Voltage.Thought I brought that up.

author: fable
author_rank: Regular Contributor
timestamp: March 26, 2014, 07:00:42 pm
content: Hi.I think u will need to remove overcurrent protection on ccfl driver ic.Look at the datasheet for that IC and u will figure out how to do it.I removed this protection on loots of monitors (3 of them are mine and after 2 years they still work ).If u need more help put the picture of the board or name of the IC.Sorry for my bad english.

author: Mike89
author_rank: Newbie
timestamp: March 26, 2014, 07:45:28 pm
content: This turned out to be just too much for me, I ended up tossing the monitor. A new one only cost me $150. I had read on the bulging capacitors and thought I would give it a try to see if that was the case and then would attempt fixing it. After seeing not the slightest trace of any bulging capacitors I figured this job had just become beyond my knowledge and means. The blue light staying on even when monitor went out (apparently monitor thought it was working when it wasn't) also made me think this problem was more than the typical blown capacitors. After reading more I even tried to get to the lamps but that was a futile exercise. Thanks for the feedback, I wish I would have gotten into this field. But as it turns out I never did and I don't even own a soldering iron so I am a complete rookies rookie. One of you teckies could have handled this monitor but this one was way beyond my pay grade. It's in the trash can right now in pieces and as I was walking away, I had to stop and look back cause I swore I heard it laughing at me. Heh heh

author: Shock
author_rank: Super Contributor
timestamp: March 26, 2014, 08:42:46 pm
content: Don't worry you're not alone, I think probably everyone has at least one thing they could not fix at one time or another.

author: granz
author_rank: Regular Contributor
timestamp: March 27, 2014, 01:51:00 pm
content: Quote from: Mike89 on March 26, 2014, 07:45:28 pmWell, if it makes you feel better, I have several broken things taking up space in my basement waiting for repair. By tossing it you won't go down that path of collecting junk. Considering the cost of monitors these days, I think you made the right choice. It might be worth it if you already had the equipment, but not if you had to purchase it just to fix a $150 monitor

author: GreyWoolfe
author_rank: Unknown
timestamp: March 27, 2014, 05:53:39 pm
content: Granz, must be nice to have a basement. Here in Florida, there is no basement. If I had one, it would be a swimming pool. Water table here is 34" below ground. I agree on collecting junque. Tomorrow is recycle day, so I am going to put a bad Dell OptiPlex GX270 computer and an old Lexmark Optra M series printer on the curb. The lexmark works, but needs charge and transfer rollers and a new toner cartridge. I have too many printers here so it has to go. Someone will be kind enough to remove them before the recycle people get here tomorrow morningI would have loved to tackle that monitor. Mike89, it WAS laughing at you.

author: granz
author_rank: Regular Contributor
timestamp: March 27, 2014, 09:23:08 pm
content: Quote from: GreyWoolfe on March 27, 2014, 05:53:39 pmHere in New England the basements can fool you by appearing to be nice safe storage spaces, and then suddenly become a swimming pool without much notice.Could provide a good reason to clear out the old junk though if it gets completely water logged.

author: GreyWoolfe
author_rank: Unknown
timestamp: March 28, 2014, 12:25:04 pm
content: I'm from New Jersey and we had a finished basement. In typical Italian fashion, when Dad did the work, he installed a complete second kitchen. The house was very old and had a very thick stone foundation. It was always cool in the summer time and Dad installed baseboard heat for the winter. That house was sold over 30 years ago but that was the house I grew up in and I still miss it.

author: christos
author_rank: Regular Contributor
timestamp: March 28, 2014, 05:59:28 pm
content: i had the same problem..it was the small lamps at the top and bottom of the monitor..they where burnd..i just ordered new lamps and it works now...if you adjust the brightness to minimum..it will start ..but it will happen again untill the lamps are dead...

author: GreyWoolfe
author_rank: Unknown
timestamp: March 29, 2014, 02:04:04 am
content: Also try using f.lux. It will brighten and dim your monitor brightness as the day passes. I don't know if you will like it but it might be worth a try. I personally like the dimmer monitor at night.