Cq40 dim display

[ry x hunter]

Hi guys.. I received this laptop cq40 with dim display.. I thought it was a back light problem but suddenly its not.. Here are the first aid i try..

Try other lcd- not good
try other inverter-not good
try other flex cable not good

i decide it was a board problem.. I check input voltage on inverter and it was a 19 volts present but 1 thing i notice, the 3.3 volts on pin 30 on jlvds1 connected on inverter was missing.. I locate the path where 3.3 came from and i found u30 sio chip pin number 21 and no 3.3 volts is present..

Can anyone help me how to decide which parts need to replace.. Thanks ypu guys..

[ry x hunter]

Re: Cq40 dim display

here are the parts i mentioned..

[dj_ricoh]

Re: Cq40 dim display

i did try in a post to give 3.3v to a pin like that and it start the light but i had problems like :
it gives a red tone on the screen.
so i guess it was the SIO chip problem.

try to Inject voltage there; there are many 3.3v that starts with the notebook.
inject or solder a wire there.

[ry x hunter]

Re: Cq40 dim display

i did try in a post to give 3.3v to a pin like that and it start the light but i had problems like :
it gives a red tone on the screen.
so i guess it was the SIO chip problem.

try to Inject voltage there; there are many 3.3v that starts with the notebook.
inject or solder a wire there.

sir can u give me a parts that give 3.3 volts to inject on 3.3 volt on that pin?

[dj_ricoh]

Re: Cq40 dim display

probe around the connector dude!

power up the notebook and check.
i polish a set of probes so they can be like a nail.(TIP)

[ry x hunter]

Re: Cq40 dim display

probe around the connector dude!

power up the notebook and check.
i polish a set of probes so they can be like a nail.(TIP)

ok sir.. i try.. thanks a lot for your advice and info sir..

[dj_ricoh]

Re: Cq40 dim display

post back when you find a 3.3V.
do you have Lab PSU?

[ry x hunter]

Re: Cq40 dim display

post back when you find a 3.3V.
do you have Lab PSU?

what do you mean on lab psu sir?

[lezsimply]

Re: Cq40 dim display

Like these...

http://www.ebay.com/sch/Power-Supplies-/50967/i.html

[dj_ricoh]

Re: Cq40 dim display

the last one with no BL i use the psu to see where to put 3.3V
its good! very good tool!
even the cheap one will do the trick!

[ry x hunter]

Re: Cq40 dim display

the last one with no BL i use the psu to see where to put 3.3V
its good! very good tool!
even the cheap one will do the trick!

i measured 3.3volts on pu102 the pin 1 give 3.3 volts but this is always voltage.. i thouht they can damage the board when i connect to this pin right?

[atsio]

Re: Cq40 dim display

Check voltage on pin 112 of U30. If voltage exist problem with U30, if not, problem with MCH.
To supply 3.3v, get voltage from Q7 pin 3 (source pin)

[ry x hunter]

Re: Cq40 dim display

Check voltage on pin 112 of U30. If voltage exist problem with U30, if not, problem with MCH.
To supply 3.3v, get voltage from Q7 pin 3 (source pin)

sir there is 3.6 volts on u30 pin 112.. now i try to put jumper on q7.. thanks sir

[agrawal.abhijeet]

Re: Cq40 dim display

I repaired one presario v2000 with inverter problem, in it inspite of 3.3 v i provided 5v to pin no 2, this enabled the inverter ckt and hence the ccfl lit up.

[atsio]

Re: Cq40 dim display

I repaired one presario v2000 with inverter problem, in it inspite of 3.3 v i provided 5v to pin no 2, this enabled the inverter ckt and hence the ccfl lit up.

Yes, you can do that in some inverters. But you do not know the specs of that specific inverter.

[atsio]

Re: Cq40 dim display

Before doing the bypass, I should reflow U30. Maybe this will bring back the 3.3v to the enable pin.

[ry x hunter]

Re: Cq40 dim display

Before doing the bypass, I should reflow U30. Maybe this will bring back the 3.3v to the enable pin.

actually sir that board is working fine before.. the only problem is in the dc port..after i repair dc port i try to connect lcd connector to the mainboard but i forgot to disconnect the power adapter.. when i connect lcd to the mainboard the charging indicator goes off and unable to power on until i try several attempt to power up until the power is back but unportunately disply become dim..

[ry x hunter]

Re: Cq40 dim display

Check voltage on pin 112 of U30. If voltage exist problem with U30, if not, problem with MCH.
To supply 3.3v, get voltage from Q7 pin 3 (source pin)

sir big thanks to you.. i follow your instruction and display become ok again but i have encountered another problem. windows booting is too long.. i try to replace memory and hdd but still the same..

[dj_ricoh]

Re: Cq40 dim display

i will be a idiot but ii'll say it
try a ssd?