A2141 820-01700 no power

[hgoncalves]

Hi.

I have an A2141 820-01700 with only 5V on ampmeter.

PPBUS_G3H = 12.58V

PP3V3_G3H_T = 3.329V

When conected to the U3100/200 ports, the ampmeter keeps rebooting (on/off).

However, I can't find nothing with strange diode values on cd3217s

Can you help?

 

[2informaticos]

Any history available?
Did you test the machine with charged battery?

Compare diode mode readings between J3300 and JB500.
S-UEM2 helps a lot here:

S-UEM2 Mac USB-C and EDP meter

S-UEM2 is a tester for USB-C and EDP connector of MacBook logic board

sofixshop.com

 

[hgoncalves]

Hi.

I followed your suggestion and bought the S.-UME2 (TKS). However, I'm not sure how to interpret the results. Can you help?

I've replaced U3200 and now I've got 20V, but 0A.

Already tried with a good battery, but still no power.

Can it still be related with U3200?

 

[2informaticos]

On the second photo, you have higher readings on pins 57 & 58; marked with red arrow pointing up.
You should check with multimeter (diode mode) directly on the MLB.
Sometime bad connections lead to wrong readings on S-UEM2.

 

[hgoncalves]

Hi.

Now I have 20V, but 0.1A

No big coils seams shorted, nither any NAND.

PPBUS_G3H - 12.59v
PP3V3_G3H - 3.3V
PP5V_S5 - 5.5V

PP3V3_S5 - 0V and 0.327 on diode reading
PP5V_S4 - 0V and 0.200 on diode reading

Can you help?

 

[2informaticos]

Do you get G3S and SSD voltages?
It is recognized in DFU mode?

 

[hgoncalves]

Hi.

PP1V8_G3S = 1.799V
P5VG3S_EN = 3.374V

P1V8_LX0_SSD0 = 1.8V
P1V8_LX0_SSD1 = 1.8V
P0V9_LX1_SSD0 = 0.9V
P0V9_LX1_SSD1 =0.9V
PP2V5_NAND_SSD0 = 2.5V
PP2V5_NAND_SSD1 = 2.5V

It is recognized in DFU, but fails with an error "Unexpected device state DFU (error 4014). Other times gives the error: Gave up waiting for device to transition from Recovery state to Recovery state. [com.apple.MobileDevice.MobileRestore – 0xFCD (4045)] and enters Recovery mode.

However, now, on ampmeter It has 20V, and starts to pull amperage, but always increasing consume steadly. It stars on 0A and goes to around 2A with battery connected without ever power on

 

[2informaticos]

Short to ground 3V3_S5 then try again DFU.

 

[hgoncalves]

Hi.

I've shorted 3V3_S5 to ground, but had the same DFU error.

 

[2informaticos]

Your problem may be T2, or SSD...

 

[hgoncalves]

Hi.

Is there any way to be sure witch one, or at least know the most probable one?

P.S. With the board assembled and with battery connected, using the IF cam, I see T2, L7030 and Q7030 getting hot, but L7030 has 12.34V on CHGR_PHASE2 and 16V on CHGR_PHASE1

Can it be Q7030?

 

[2informaticos]

STOP checking DC voltage on input pin of a coil from buck converter.

 

[hgoncalves]

Understood.

Is it possible to replace T2 chip, with another one from a same model number donor board?

 

[2informaticos]

Yes, but must be compatible version with SSD size.