Recent content by overshoot

I have since replaced the board for the customer and have time to investigate this board. Before I go for replacing the NANDs, I have made some more measurements and one rail that seems off which is PPVDD_S1_DISP and sits at .776V FlexBV says that it should be at .942V This rail seems to go to...

The battery is charged. I was able to boot up the computer using a known good motherboard and battery was charged at 70%. Everything else works other than the MB. I will try target disk mode. Thanks.

Hello, I have that board where the data is important that is boot looping and I haven't tried DFU revive/restore yet. Screen comes on, no Apple logo, and will turn off after around 10 seconds and does that in a loop. When the board turns off, the SSD_PMU_RESET_L goes low. PPBUS is stable at...

Following down the rabbit hole, I went to check UT410 and the diode mode values are ok. I am getting 0V at IPD_PWR_EN_GATE_R and 0V on pin 4 of UT480. UT480 has good diode mode readings as well but 0V on IPD_PWR_EN which comes from the MPMU. I need help from here please

I made some progress on this board and got it to DFU mode but it failed with 4042. Following that, I've checked all the SSD rails and they were all present and steady for 30 secs, no prob. Then I went back at it to measure some voltages and found something interesting. The PPVOUT_KBDLED is...

I do not have a working board for this model. What if I am already getting 20V with the battery plugged in, does that rule out a CD3217 fault? Also I can't get the machine to go DFU and trackpad won't click.

Yeah no, I already checked to see if the board was in recovery mode and it’s not. The measurements are done with the board alone, out of the case.

Hello, I've got this board that stopped working after, that's what the customer has reported, the trackpad stopped clicking. Board looks pristine, no liquid damage that I can spot. I was getting 20V 0.01A with battery plugged in. Without battery, I am now getting 5V with 0.1A current drawn...

Hello, I have that 14" M1 board that was previously liquid damaged and repaired. As I've received it, PP3V8_AON is at 1.5V fluctuating up to 1.7V and PPBUS_AON is at 12.25V. I am getting a .16V drop to ground on the PP3V8_AON line and when injecting voltage, the amperage drawn is minimal...

I've got .313V with the resistor in place and .465V without.

unfortunately not as client said it stopped working out of the blue. I've also checked IPD_LID_OPEN_1V8 and it's present at 1.8V I've checked again that lpdp_int_hpd_3v3_conn and it's not even pulsing. What could cause that signal to be missing?

Hello, This is a board issue. I've tested with board another good working screen, same symptoms. Client's screen works with test MB. Works with external display as a secondary monitor. Here are some measurements: edp_panel_1v8_en = 1.8V pp3v3_sw_lcd = 3.3V pp5v_sw_lcd = 5V bl_pwr_en = 0V...

Well I can answer my own question. Yes fixing the other side USB-C circuit did indeed allow the computer to boot up right away without going through DFU. Case closed.

I went back at it and got one side (both ports) to get 20V. The side with U3100_X and U3100_T. However the amperage jumps to 200ma and then drops to 30ma. Then the port cycles and back at 0ma and jumps to 30ma. It does that in a loop. I've tried a DFU revive and then restore but it ends up with...

Thanks! I've already replaced the chip which has 5V so far with one from a 820-01700 as I mentioned in my previous post. I've tried to get it to DFU but my other Mac doesn't see it. I am wondering if I've used the right chip or if I should transfer the pair of CD3217 with the Rom. I've used...