A2179 820-01958-A no backlight

[hgoncalves]

Hi,

I have an A2179 820-01958-A with no backlight.

Already tried known good display, without success.

It has external image, and i can see the apple logo on the internal display (very dark).

PP3V3_G3SSW_SNS = 3.3V
ISNS_LCDBKLT_N = 12.59V
ISNS_LCDBKLT_P = 12.59V

PP5V_G3S = 5.1V

PPVIN_S0SW_LCDBKLT = 12.59V

PP5V_S0_BKLT_A = 5.1V
PP5V_S0_BKLT_D = 5.1V

EDP_BKLT_EN = 3.3V
BKLT_EN_R = 3.3V

PPVOUT_S0_LCDBKLT = 54V

ISNS_LCDBKLT_IOUT = 0V

My schematic is very wrong, and where it should have R5629 it is no stuff, but PMU_LCDBKLT_ISENSE= 0V (on R5628)

Can you help?

 

[2informaticos]

"PPVOUT_S0_LCDBKLT = 54V"
So backlight circuit works.
There may be broken trace.
Do you get that voltage on the T-CON board?

Sometime DFU restore can solve this problem.
Save data first, if needed.

 

[hgoncalves]

HI.

DFU solved!

TKS