Macbook Pro 820-2850 Green Light, charges, boots off battery only, no back light

Mac-N-Sauce

New member
Ok, I just joined and have to admit i am a little intimidated! I am a rookie.
I get green and orange light on charger, boots, chimes, no back light at all.
Computer will not power on by charger alone it must have battery to power on.
Inspected back light circuit to discover R9703 missing completely. Replaced and still no back light. Do not have backlight en.
Appears as if it may have been cleaned previously so very minor evidence of corrosion anywhere
Any thoughts?
 

dukefawks

Administrator
R9703 is a NO STUFF so it shouldn't be there. How does LCD connector look? LCD cable corroded on last 3 pins? Got voltage on L9701?
 

Mac-N-Sauce

New member
I can not believe i completely missed the no stuff on the schematic. Lcd connector looks great, no corrosion. plugged in a known good screen and it came on. What could keep the old screen from working if the cable isn't damaged?
Still can not figure out why it will not boot off of the charger alone
 

dukefawks

Administrator
Obviously LCD cable or LCD is bad, it needs to come apart anyway. The no AC issue is probably around the ISL6259. Check the sense resistor circuits.
 
Top