I-Inc IF281D Display Problem

[AloofOne]

Hi all I'm new here and while searching for internet for possible solutions to my problem i noticed this great forum and thought i would ask for any advice that might help me solve this issue.

I have an I-Inc 28inch monitor that has a display/power problem. One day while i was at the office i tried turning the monitor on and was working fine for about a minute or so until it shut itself down. I turned the monitor back on again and this time it shut down in about 20secs, a third time and it shut down almost immediately. I tried different power cables and different inputs but get the same result.

I called the manufacturer who promptly told me the monitor is out of warranty and could not help me. So instead of trashing this nice monitor i was hoping to repair it. Any advice would be appreciated =).

[jetadm123]

Re: I-Inc IF281D Display Problem

Please post a photo of the entire inverter board. A overhead shot is preferred because that allows us to see all the components. And take your photos as if you're asked to read the printing on the board itself. Your previous photos of the printing at an angle and sideways makes for akward viewing.

[AloofOne]

Re: I-Inc IF281D Display Problem

Here is the inverter board picture. If you need more let me know. again thanks for your help.

[jetadm123]

Re: I-Inc IF281D Display Problem

What you're showing is the power supply. The inverter is the board that generates the high voltage for the backlighting. In your third photo, it appears to be the board at the very top with all the transformers on it.

[AloofOne]

Re: I-Inc IF281D Display Problem

i removed the inverter board from the monitor but it has some plastic cover over which is very difficult to remove.

[retiredcaps]

Re: I-Inc IF281D Display Problem

I turned the monitor back on again and this time it shut down in about 20secs, a third time and it shut down almost immediately.

You might be experiencing 2 seconds to black. Read through posts #19 and #20 at

https://www.badcaps.net/forum/showthread.php?t=10419

2 seconds to black can be (in no particular order)

a) bad caps
b) bad inverter transformer
c) bad ccfls
d) bad ccfl wiring (especially the return wire)

[AloofOne]

Re: I-Inc IF281D Display Problem

thank you, i'll read through the posts.

[AloofOne]

Re: I-Inc IF281D Display Problem

hello again, sorry i haven't replied in some time i was sick last week and haven't been able to do any testing. I was able to borrow a friends DMM of decent quality so i'm hoping my readings with be accurate.

i tested the monitor yesterday by turning it on and just leaving it alone for awhile. It went into standby (orange light) and stayed on for hours as long as i didn't try to input a signal in which case it would turn off shortly after. i noticed that on the video board 1 of the chips (ic controller?) had a solder bridge. Not sure if that has anything to do with my problem. Anyways i checked all the caps and they seem fine in appearance but from reading the forums here i know that they can still be bad.

Any advice from here would be appreciated.

[jetadm123]

Re: I-Inc IF281D Display Problem

Well, it appears that the printing on the power board indicates the output voltages are 5v and 24v. Correct? The 24v should feed the inverter and the 5v supplies the video board. I suggest piecing everything back together and measuring for these voltages at the wiring harnesses connected to each board.

[AloofOne]

Re: I-Inc IF281D Display Problem

Says on the board. model# FSP217-4F02, DC Output +5.0V -1.5A, +5.0V - 4.35A,+24.0V - 5.5A, +12.0V - 4.77A.

i've also taken some readings on the board prior to your post i hope they help.
Q1 = 30.01
Q2 = 30.10
Q3 = 31.65
Q4 = 28.35
QS1 = 29.99 2 on that heat sink the other read 000.1
F1 = 000.1-000.2 (fuse)
D10 = 0.610 / 0
D8 = 0.423 / 0
D5 = 0.617 / 0
D7 = 37 - 40 but doesn't look like a diode must be mislabled

Hope this helps some.

How do you test the voltage at the wire harness?

[jetadm123]

Re: I-Inc IF281D Display Problem

To measure the voltage off the wiring harnesses, set your meter to DC volts, place your black probe on a good ground point. Each wiring harness is plugged into a connector on the power board with the other end plugged into the inverter, logic board,etc. With your red probe, try measuring the bare wire coming out the back of that connector. Be careful, as those wires look like their close together. If it's easier to get to, then try measuring the voltages from underneath the board.

[AloofOne]

Re: I-Inc IF281D Display Problem

Okay i'm back with more information.

I took some readings from video board with the power plugged in and connected the power board.

Rail 1 = 5.09

Rail 2 =
Yellow = -21.7
Orange = -21.7
Red = 5.07
Green = -21.7
Brown = -21.7

here is a photo of the area i took readings from

[retiredcaps]

Re: I-Inc IF281D Display Problem

Rail 2 =
Yellow = -21.7
Orange = -21.7
Red = 5.07
Green = -21.7
Brown = -21.7

If you are getting negative voltages, you are probably using the wrong ground point. Use a screw (like the one by CN4/CN3) on the main board and remeasure.

[retiredcaps]

Re: I-Inc IF281D Display Problem

i've also taken some readings on the board prior to your post i hope they help.
Q1 = 30.01
Q2 = 30.10
Q3 = 31.65
Q4 = 28.35
QS1 = 29.99 2 on that heat sink the other read 000.1
F1 = 000.1-000.2 (fuse)
D10 = 0.610 / 0
D8 = 0.423 / 0
D5 = 0.617 / 0
D7 = 37 - 40 but doesn't look like a diode must be mislabled

Hope this helps some.

Regarding the way you are reporting the numbers above. See

https://www.badcaps.net/forum/showpo...2&postcount=31

[AloofOne]

Re: I-Inc IF281D Display Problem

i used the black wire from the set as ground. i'll try using a screw. As far as the reading i just copied what i saw from the DMM which has autorange on. do you need me to list which is a resistance test or diode test? i'm not a pro at using this meter. =)

[AloofOne]

Re: I-Inc IF281D Display Problem

Test 2 using a screw

Rail 1 = 5.14V

Rail 2
Yellow = 0
Orange = 0
Red = 5.14V
Green = 0
Brown = 0
Black = 21.8V

[AloofOne]

Re: I-Inc IF281D Display Problem

Here you go.

Q1 = 30.01 (resistance)
Q2 = 30.10 (resistance)
Q3 = 31.65 (resistance)
Q4 = 28.35 (resistance)
QS1 = 29.99 2 on that heat sink the other read 000.1 (resistance)
F1 = 000.1-000.2 (fuse) (Resistance)
D10 = 0.610 / 0 (diode test mode)
D8 = 0.423 / 0 (diode test mode)
D5 = 0.617 / 0 (diode test mode)
D7 = 37 - 40 but doesn't look like a diode must be mislabled (resistance)

[jetadm123]

Re: I-Inc IF281D Display Problem

Test 2 using a screw

Rail 1 = 5.14V

Rail 2
Yellow = 0
Orange = 0
Red = 5.14V
Green = 0
Brown = 0
Black = 21.8V

It looks like the power board is outputting 5V and something close to 24V. I suggest connecting the boards back together and measuring the voltage at each pin of the devices circled in the photo.

[AloofOne]

Re: I-Inc IF281D Display Problem

ok here are the results

smaller chip =
2.2Vdc
1.805vdc
3.304vdc

Larger Chip=
2.3vdc
3.304vdc
5.14vdc

I take another photo of the video board so its easier to see.

[jetadm123]

Re: I-Inc IF281D Display Problem

The voltages look good. With a computer connected to the monitor, shine a bright light at an angle against the monitor screen to see if you can see an image.