Monitor 15" GOLD L-151

[badrianiulian]

Re: Monitor 15" GOLD L-151

Thanks retiredcaps I actually looked at that on the part
Perhaps I was just hoping too much that it was a 3v running low!

Badrianiulian ( hope I dont have to type that often)

I meant for you to check the voltage on them in position unless you have an esr meter taking them off wont show much.

The measuring part I intent to do is with a capacimeter type CM9601 and measure the capacity...

On the other hand I could replace all the capacitors (since they're not that expensive) on the main board and U13 (24LC16B) and U10 (24LC02B) since I read once that a bad memory could cause this simptom... any thoughts?

[selldoor]

Re: Monitor 15" GOLD L-151

When you detach the main board from the (Audio) Board is there still 12 volts on the
inverter?- If the cable is fairly standard perhaps it has 12v gnd x 2 on/off and dim.

If you have 12 volts and can apply 3 volts using a battery to the on/off perhaps the lights will come on?

[badrianiulian]

Re: Monitor 15" GOLD L-151

When you detach the main board from the (Audio) Board is there still 12 volts on the
inverter?- If the cable is fairly standard perhaps it has 12v gnd x 2 on/off and dim.

If you have 12 volts and can apply 3 volts using a battery to the on/off perhaps the lights will come on?

Checked with the main board detached and there is 12V on the inverter. However the 0,16V is gone.
Also checked with 3V to the on/off... still dead

[badrianiulian]

Re: Monitor 15" GOLD L-151

Hello brain786786 .. I do not understand what you mean by your replies...

[selldoor]

Re: Monitor 15" GOLD L-151

He is a spammer - ignore it

[selldoor]

Re: Monitor 15" GOLD L-151

Checked with the main board detached and there is 12V on the inverter. However the 0,16V is gone.
Also checked with 3V to the on/off... still dead

How did you decide which was the on/off

[badrianiulian]

Re: Monitor 15" GOLD L-151

How did you decide which was the on/off

Well you got me there... the on/off as I thought and tested was the on/off button... By you asking this question I figure I may have been wrong?
Tested with minus to the ground, one of the button's contacts, and the positive on the other contact.

[selldoor]

Re: Monitor 15" GOLD L-151

Haha communication breakdown I think?
The three volts has to be applied with the negative to ground and the 3volts+ to the on/off PIN (perhaps the orange wire pin on the inverter board with 0.16v but its only a guess.

[badrianiulian]

Re: Monitor 15" GOLD L-151

Haha communication breakdown I think?
The three volts has to be applied with the negative to ground and the 3volts+ to the on/off PIN (perhaps the orange wire pin on the inverter board with 0.16v but its only a guess.

You asked and I tested (with vga signal 800x600 and 1024x768) :
Plugged in 12V and then tested with 3V on the orange wire: the backlights are starting up with a white screen.
If I press the Power button in this configuration, I get some lines both horizontal and vertical that flicker.
Pressing the Power button again reverts the image to the white screen.

[selldoor]

Re: Monitor 15" GOLD L-151

OK we are getting a bit nearer. - Wasnt expecting any picture as I asked you to detach the main board?

So there is 5 volts and 12 volts we know the lights work (I know you tested them already) with this set up so the inverter board is good and the Audio Board is probably good. We need to find out why the Main board is not sending the 3 volts.

Can you take it off the frame and post a very clear picture of the back of it.

[badrianiulian]

Re: Monitor 15" GOLD L-151

Pictures ... front and back of the main board detached

[Rtech]

Re: Monitor 15" GOLD L-151

Would hope that you have been looking for a replacement board,since Post 14,as it would seem that you have done every test you have been asked to do,and usually, unless the fault on these boards are Caps,Fuses or Voltage Regulators,then the only solution is replacement.

[selldoor]

Re: Monitor 15" GOLD L-151

Can you have a look at U9 which I think is an eeprom. Looking at the picture the
contacts at top and bottom line up exactly with the spaces but down the sides they dont. I am wondering if its has been taken out and put back the wrong way round?

Is there any sort of marking on it, a dot or an indent or a cut off corner to help?

[badrianiulian]

Re: Monitor 15" GOLD L-151

Checked the bios type looking eeprom and it is in the right position the dot is in the right corner.. does't fit in the slot if you turn it around

[selldoor]

Re: Monitor 15" GOLD L-151

Thats a pity

Running out of ideas!! and I doubt if you will find a replacement board. Are you up for rechecking some components? Just say if you want to give up.

In This thread
https://www.badcaps.net/forum/showth...t=25282&page=2

start at post 20 it is about testing voltage regulators
out of circuit and also mentions that although it may test ok it could fault when a load is applied and it suggest using a resistor in the circuit to provide a load.

[badrianiulian]

Re: Monitor 15" GOLD L-151

Thats a pity

Running out of ideas!! and I doubt if you will find a replacement board. Are you up for rechecking some components? Just say if you want to give up.

In This thread
https://www.badcaps.net/forum/showth...t=25282&page=2

start at post 20 it is about testing voltage regulators
out of circuit and also mentions that although it may test ok it could fault when a load is applied and it suggest using a resistor in the circuit to provide a load.

Read a bit... If i stick in a 100 ohm resistor directly on the main board to test the regulators will it be enough? Or should I take them out one by one and test them with a load of 100 ohm and a 5v/9v supply?

[selldoor]

Re: Monitor 15" GOLD L-151

Unfortunately you would need to take them out - which i know is not easy - I was hoping a few others would stick with us on this case - If you like ,wait and see if anyone else chimes in with anything missed or as you suggested change all the caps on the main board. Cant remember did you test any diodes.

[badrianiulian]

Re: Monitor 15" GOLD L-151

The taking out is not going to be that bad since i got a hot air soldering station available
I did check some diodes... on the main board all 3 diodes test with same values (D4,D5 and D6)
On the "Audio board" I checked one (D008)
Checking with no power with a multimeter the 3,3 regulators on the main board I only get different results with U1 between GND-OUT and OUT-GND; the other values are the same as U5 and U2; U5 and U2 measure the same between OUT-GND, GND-OUT, IN-GND, GND-IN, OUT-IN, IN-OUT.