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Hello all, I got this weird laptop that supposedly wasnt turning on. I let it charge for a while using a known working motherboard and it eventually turned on. With its original MOBO I notice it charges but does not show the typical lightning bolt on the battery icon, it shows nothing at all...

So as I mentioned in another thread, i'm new to specializing on apple products but old to being in electronics service and repair. One of the things that are becoming very apparent to me on doing this field of work is that parts can be expensive because they are related to the apple name. I I...

Alright, will do. Thank you!

I'm trying to set up a bench power supply to power all my logic boards under test using just the adapter tip from a magsafe charger. See this link https://www.amazon.com/Droya-Repair-...ateway&sr=8-50 What I want to know is if those tips will report as 85W or anything lower which would be a...

Appreciate it. I still have some way to go learning the specifics of macbook board repair but my previous experience is carrying over well. I'm in the south side of Chicago.

I have just gotten into board repair. Have been a technician for other electronics for several years but am just now specializing on laptop/macbook boards. I'm thinking of doing a flat rate. What would be a good charge for macbook board repairs? I see may mail in places will charge anywhere...

I figured. Im happy i could narrow it down to the fault though. This is what mattered to me most. Thanks for all the help!

Thought I had replied already. I removed and bridged U8005. Fault persisted. The only thing that solved it was disconnecting L1290. L1295 is omitteed. Tried removing the coupling caps. It looks to me like the PCH is bad as that is all that is left connecting here.

Yes I did. I have managed to inch closer to the fault. When I ground the enable pin to U8005 1.05V PCH HSIO Switch all the rails turn on, including some of the ones that didnt turn on before like L7310 and L7320 which are making 1.05V volts. The offending line seems to be PP1V05_S0SW_PCH_HSIO...

Tried that but no luck. Shows same amount of current consumption and everything.

Hi friend, check out my thread titled 820-0064 need U8080. Your issues sound quite similar to mine. Esp the part about the pulsing PPBUS_G3H. On mine i thought it was U8080 but have found other issues. I was wondering if you could help me too actually and seeing if too the right of your audio...

My updates for today. I figured out what i think is the SMC bypass routine. Put everything back together and connected the magsafe charger while holding down the power button for a while. Nothing happened. Tried SMC reset too, with and without charger connected. With the charger i can see the...

Im getting all coil voltages except L7701, L3095, L2920, L7310, and L7320. I don't know how to do SMC bypass. Please explain? These last two produce PPVCC_S0_CPU 1 and 2. These two i mentioned before as reading 13 ohms to ground. I took out one of the current sense resistors and on CPU side it...

I got fan spin!!!! I removed the enable signal to U8030. It's going to be a bitch figuring out why that helped though. No ground on this rail. This creates PP3V3_S0 No liquid spill. Not sure what the history is. Looks spotless.

My latest finding Figuring that maybe the short isnt on the 5v line and that perhaps the activation of that 5V line is turning on an IC or transistor that shorts out a different unrelated line I cut the incoming 16.5v and put an ammeter there. The board idles at 20mA and when it peaks it hits...

Okay i measured it. L3095 and L7701 are the only two coils that don't tick. All other coils peak at around .52 or so then go off. L7520 peaks at around 1.8v then disables. L7560 is makiing 3.3V. L7130 is making 8.5V. Neither of the coils that do not pulse show low resistance to ground. LL7701 is...

Thank you, I'll give that a try. Will report later.

What I'm wondering is if maybe one of the buck or boost circuits that feeds from PP5V_S0 is the one with a short on it's output. I snooped around a but so far nothing has happened. My theory was that if a dependent buck converter was drawing excessive current, or perhaps any other circuit where...

So how much of a bad idea would it be if I just forced 5V into this missing rail and watch for smoke or heat? I plan on hooking a usb charger up to it and limiting the current with an incandescent bulb.

Looks like youre right, i get the same pulsing after hooking those two lines up. This time im seeing a resistance between PP5V_S0 and GND. 63K Ohm when black is on ground, 32Kohm when red is on ground. This is still high for a 5V line. It would be great if someone with a working board could give...