VPCF22J1E no picture in LCD

[lefos]

Hello,

I really need your help with this one. Has picture on vga output normally but it doesn't have in the lcd panel. Neither backlight. I have 5V on the lcd. I have tried reflow on chipset + gpu with no result. Anyone had the same problem before or can give any advice please?
Motherboard is MBX-243

Thanks

[atsio]

Re: VPCF22J1E no picture in LCD

Give voltage on all pins of LVDS connector.

[lefos]

Re: VPCF22J1E no picture in LCD

Hello thanks for your reply,

You mean to give all necessary voltages in order for the panel to work?

[atsio]

Re: VPCF22J1E no picture in LCD

No, measure the voltages on all pins of the lvds connector. There isn't a schematic yet on the internet but it will give us an idea of what is happening with the lvds signals.

[lefos]

Re: VPCF22J1E no picture in LCD

Hello,

Thanks for your reply. Well it has the necessary power voltages on it but I don't have data on the connector on the motherboard side.

[lefos]

Re: VPCF22J1E no picture in LCD

Odd thing is that I have already ordered a motherboard with it I have the same problem..
I don't have the same panel but I have checked with smaller size which also has the same problem. Any ideas?

[atsio]

Re: VPCF22J1E no picture in LCD

Hello,

Thanks for your reply. Well it has the necessary power voltages on it but I don't have data on the connector on the motherboard side.

Which are the necessary voltages and how you figured there is no data?

[lefos]

Re: VPCF22J1E no picture in LCD

Hello again,

Sorry for being late on the response but I was expecting a news lvds cable for check. Nothing changed. If you power on the laptop you can see something like trying to have picture but no backlight and no picture at all. Just the screen gets a little bit darker.
On the lvds connector I have mostly only 5volts and 3.3v on a few pins. The rest are 0.
I am starting to think that the problem is from the panel?

[atsio]

Re: VPCF22J1E no picture in LCD

Your LVDS connector is 40pin labeled CN13?
If yes, you should have 3.3v on pins 31,32 and 33, 5v on pins 34,35 and 36 and around 1v at pins 1 to 17 (except pin 9) which is ground.
If your screen is edp you should check for voltage on pins 18 to 28.

[lefos]

Re: VPCF22J1E no picture in LCD

Hello,
It is labelled CN44. The connector is 50pin.

[atsio]

Re: VPCF22J1E no picture in LCD

I hoped the schematic I found would help. It's better to open the panel and measure on the lvds connector on the panel. It is more standard on new led screens. I imagine the panel is 16.4 inch.

[lefos]

Re: VPCF22J1E no picture in LCD

Yes it 16.4 . Have already done that with the same result unfortunately. The odd thing is that panel is trying to do something but with no result. I have tried other panels (smaller inches , different brands), I don't have the same here, but nothing.
Very strange defect.

[atsio]

Re: VPCF22J1E no picture in LCD

I am attaching the datasheet of the chi mei 16.4 (Sony usually uses it but all lvds connector on the 16.4 panels will have the same pinout) and check again for around 1volt on data pins, LED PWM, LED EN, LED_VCCS and offcourse for 3.3v on pins 2,3,4.

[lefos]

Re: VPCF22J1E no picture in LCD

Hello,

I have checked on the panel side
pin 1 , 2 = 0
pin3:3.16
pin4: 5.09V
pin5 :0
pin 6:4.80V
pin 7: 0
all rest pins = 0 till 40:=19.22V

[atsio]

Re: VPCF22J1E no picture in LCD



You shouldn't have any 5v and also 19v on data pins.
Which panel do you have?

[lefos]

Re: VPCF22J1E no picture in LCD

It is N164HGE-L11Rev C1 Chimei.
It is driving me nuts.

[atsio]

Re: VPCF22J1E no picture in LCD

Although LVDS connector does not much I am passing you the schematic of the VPC F series MBX-215 to have a look at it. In their photos they look the same (MBX-243 and MBX-215).