Recent content by tlough75

Did you read my post? I didn’t say anything about the fact that I injected voltage. I measured for shorts...using resistance mode with the power off.

I have on the bench a liquid damaged 820-00840 that had cola spilled on it. the 2 areas that were hit were U7650 and U7220. both PPBUS_G3H and PPBUS_G3H_CPU are 0.8 ohms to ground. Should I even bother injecting 1V, or should I kiss this one goodnight? I did replace U7650, C7651, R7865, C7689...

I re-soldered U8900 and it is no longer kernel panicking or crashing. Stress tested for 2 hours and it seems to be resolved. Thank you for your help.

Update: Machines 2 & 3 are fixed with U8900 reflow. Machine 1 still having issues.

Machine 1: Screen goes black but GPU VCORE stays at 900mV. Shows kernel panic. NO Liquid damage or drops Machine 2: Screen goes black and GPU VCORE goes to 0V. NO known Liquid damage or drops. No Kernel panic Machine 3: Randomly freezes and requires a restart. No known liquid damage or drops...

No, I only resoldered U8900 on the first one. I guess I could do the other two as well.

I'm assuming since I still get PPVCORE_S0_GFX_PH1 & PH2 even when screen goes black that the GPU is faulty. On the second 820-3332 when the screen goes black, GPU VCORE drops to 0V, so I would think that is U8900. Am I correct in my thinking?

I actually have 3 of these machine. Early 2013 15" Retinas with the same issue. On #2 though, when screen goes black, The GPU VCORE goes to 0V so I am assuming U8900 may have broken solders.

I used HWMonitor and it says the SSD has 63% service life left, though I am not sure if that is helpful.

I have on the bench an 820-3332, so it is an Early 2013 15". the first time I saw it on my bench the screen would randomly flicker and the laptop would crash. I resoldered U8900 and it seemed to fix it, but a week later it is back on my bench. According to the customer, after it is running for...

Just to reiterate: PP3V3_SUS is currently at 1.1V. This signal is created by U8200 via pin 3. U8200 is supplied by PP3V3_S5 on pin 2 which is supplied from U7650, which it has 3.3V. U8200 is told to turn on by the power rail PM_SLP_SUS_L which comes from pin 238 of U1100, which by no...

Yeah, I think so. DO you know of anyone that has reballed one of these boards by hand? I do not have a BGA reball machine. I do have the stencil for this chip though.

Ok, did that and no change. I can see crap under U1100 which I assume is the PCH.

Ah ok. Well I figured Celsius, so I tried it and no change.

Is that Fahrenheit or Celsius?