(347) 552-2258 [email protected]

820-00165 no video???

K

Kyle93

Active member
This was a donated macbook. Installed a SSD, loaded OSX and while charging the battery up the screen just randomly went out. Tried a good known test screen as well but still no image or backlight. Chimes and has USB activity. 0V on EDP_Panel_PWR

Board has no liquid damage. What to check next?
 
2informaticos

2informaticos

Administrator
Staff member
Check for corrosion near LCD connector.

Do you get 3V at pins 18/19, at least in the first seconds (when chime)?
DP_INT_HPD should go to 2.65V at same time; if LCD connected.
 
K

Kyle93

Active member
Yes no corrosion near LCD connector,

0v at pins 18/19 even at first few seconds when chime

DP_INT_HPD remains at 0V
 
2informaticos

2informaticos

Administrator
Staff member
"0v at pins 18/19"
Check diode mode to ground, w/ LCD connected.

Test for voltage there w/o LCD connected.
At least few seconds must appear.
Keep voltmeter connected, pulg in the charger and monitor voltage 10s in that point.
 
K

Kyle93

Active member
0.460 diode mode w/ LCD

Voltage remains at 0 with meter connected from time charger is plugged in. Also measured at L8304
 
K

Kyle93

Active member
EDP_PANEL_PWR also 0V

R1431 67K

Could this be bad CPU even though it chimes with usb activity???
 
2informaticos

2informaticos

Administrator
Staff member
Looks like...

PCH should enable 3V for LCD first.
If LCD replies with correct DP_INT_HPD, voltage is maintained and eDP output enabled too.
 
K

Kyle93

Active member
found a small spec of corrosion on pad 2 of C8160. Scrapped it away and now board does not come on at all. No green light. PPBUS_G3H only 8.20V

Should SMC be replaced even though no liquid damage in that area???
 
K

Kyle93

Active member
Bad IO cable was causing it not to turn on. Still 0v on DP_INT_HPD. Will heat PCH with quality flux and try ultrasonic. Afterwards is there anything else to check or hopeless?
 
You must log in or register to reply here.
Top