820-00163, MagSafe flashing green light when battery is plugged in.

cobragfox

New member
Original issue was laptop won't power on with MagSafe. Replace U7100 to correct this issue.

With the battery plugged in, the MagSafe flashes (long green, then short green, then repeat). Laptop powers up still and runs, but battery won't charge. Runs fine with only battery or MagSafe, but once both a connected, the blinking starts.

I've replaced U7100 x2 to confirm not defective. Current sensing resistors measured good and traces to U7100 also good.

Once i turn the board off, it comes back on once the MagSafe cycles through the blinks. What what i can tell, data is being sent through SMBUS_SMC_5_G3_SCL and SMBUS_SMC_5_G3_SDA.
 

cobragfox

New member
Q7155 isn't short, but measured approx. 72ohms on pins 1/2/3. Isolated the low resistance to the PPVIN_S5_HS_GPU_ISNS line. Wondering, is the normal resistance for this line as the board boots up to OS with no issue, either with battery or with magsafe, and with both (except with the MagSafe blinking)?
 

dukefawks

Administrator
Q7180 is a good suspect. Also check resistance between pins 17/18 27/28 on U7100. Is PPBUS present with charger only and what voltage?
 

cobragfox

New member
Well, power issue is resolved. Now got this weird issue where the display doesn't come on until its completely loaded the os, i close the screen to put it in sleep mode, then open the screen before the screen starts to work.
 

cobragfox

New member
Original LCD. Also it was running normally before the transistor replacement, back when I could only power up with either charger or battery and not both. Looking around the transistor area (q7130/35), top and bottom of board.
 

dukefawks

Administrator
Do a PRAM reset and test with a known good LCD assembly. Also inspect around LCD connector for knocked off parts.
 

cobragfox

New member
Same result. Even HDMI isn't working, and doesn't work even after i wake the laptop from sleep and the display starts to work.
 
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