Acer Aspire 5336 no backlight

[asem18]

Hello everyone.
Acer Aspire 5336 no backlight , current consumption 0.20amp.
The fan just sinning when i push button than off.
+5VALW / +3VALW /+5VS / 3VS is ok.
1.5VP is ok..
RSMRST pin 100 = 3.2v...
PM_SLP_S3# = 3.3v...PM_SLP_S4# = 3.3v...PM_SLP_S5# = 3.3v.
JLVDS1 = pin1/2 = +INVPWR_B+ =19v
pin 5/6 =+LCDVDD = 0v

Q36 = Pin2 = GMCH_ENVDD = 0v.

Ram slot =
Pin 199 = SPD = 3.v
Pin 203 = VTT = 075v
Pin 30 = Dramrst = 0V ( must be 1.37v)
Pin 200 = SDA = 3.3v
Pin 202 = SCL = 3.3V

PLT_RST = pin 22 = jmini = 0V
+RTCVCC = 3V

Flashing bios ( taken from the acer site ) = same issue


Is the GMCH (U23) Bad !..or should i check other components !http://www.s-manuals.com/motherboard/compal_la-6631p

[Techtiger]

Re: Acer Aspire 5336 no backlight

Q36A pin 2 resistance to ground ? For Dramrst try with another working RAM with out Dramrst PLT RST won’t work

[asem18]

Re: Acer Aspire 5336 no backlight

Thank you techtiger for your help.
i mention that i change cpu (Celeron ) but still the same issue
q36a pin 2 resistance to ground = non stable between 70/80 kohms

[Techtiger]

Re: Acer Aspire 5336 no backlight

Check U7 Ich_pwrok pin 4

[asem18]

Re: Acer Aspire 5336 no backlight

Techtiger a big thank to your help.
Yes the U7 was faulty.
1=3.3v
2=3.3v
3= GND
4=+3VS
4= 0V
I changed with another and magic is done..je te remercie infiniment.

[Techtiger]

Re: Acer Aspire 5336 no backlight

De rien avec plaisir