For $29/mo, we provide access to advanced level technicians who will answer your questions on any Macbook board related matter to the best of their knowledge promptly & walk you through how to solve your problem so you can deliver a working board to your customer.
820 3332 no liquid damage, light on magsafe very intermittently while the machine is assembled. I get green light on magsafe for a split second then it goes off when the board is pulled. I get votage starts at around 2v then drops rapidly on pins 1 & 2 @ j6900.
112.7 Ohm is way to low. It is also too high for anything to heat up when injecting voltage. So this is going to be one of those boards that you will need to pull every component on 3V42 until you find it. Could be one of the tiny caps or even inside the board. Got time to waste?
You could go over the board with heat and cold spray to see if that 112 changes with temperature to narrow down the area where the bad component is.
Duke when I measure the resistance of PP3v42 on a working board I get 108 Ohm, are you sure 112 is not good? Diode mode measurement is also nearly identical compared to my board with issues.
I have no idea what you are measuring but on a known good board I have diode mode .330 and resistance 85K. You checking this with power applied or something?
Our diode measurements are not that far off my .302 vs your .330. Your getting 85kohms, maybe i fucked up, and misread kiloohm instead oh Ohms, in that case we would not be that far off 112k vs 85k, but you said 112ohm is very low, I do not under stand how that would be anywhere close to low compared to 85k. Sorry Duke, I don't mean to be a pain in your ass, but I am very confused now.
PP3V42 on my bad board, is extremely close to the same measurements taking off of a known good working board, and a donor board I have in my drawer. What gives....
John, yes, we are both on the same page there. Duke said that 112ohm was way to low, but that is a much higher resistance then 85k. Anywho, PP3V42 on my bad board is 112kohms, sorry that was my fault for the bad info. .302v diode mode measurement and 112kohm resistance measurement. This is not too far off from the working board Duke is measuring on, and it is also even closer to a working board that I am measuring. PP3V42 does not seem to be short at all. Do you guys have any other advice?
So charger is shutting down. Q7080 is a common suspect. A good test for that is to plug in a battery that has charge in it so that PPBUS has power. Then measure on the magsafe connector if there is any voltage leaking through. Should be very close to 0V. Also check resistance on the magsafe connector, should be around 22K to GND.