Macbook A2141 820-01700

[Instafixx]

Hello,
We have a Macbook A2141. LIQUID DAMAGE. Customer must have showed it somewhere , as many caps are are removed or burnt out around UB000 and U8900 (assuming this was the region of liquid spill)

AMP Meter is Pulling 5V on all 4 Ports. (Using a 96W Charger)
PPBUS_G3H is 12.3V.

Can anyone help me out on this?

[mon2]

Re: Macbook A2141 820-01700

Check the voltage to ground of each LDO rail of the ACE (CD 321x) controllers. Each ACE controller must be working to select the 20v power delivery contract from the power adapter.

Post each measurement.

[Instafixx]

Re: Macbook A2141 820-01700

Check the voltage to ground of each LDO rail of the ACE (CD 321x) controllers. Each ACE controller must be working to select the 20v power delivery contract from the power adapter.

Post each measurement.

PPVBUS_USBC_XA at 5V
PPVBUS_USBC_XB at 5V
PPVBUS_USBC_TA at 5V
PPVBUS_USBC_TB at 5V

When the charger is being plugged in the corresponding Ports.

[mon2]

Re: Macbook A2141 820-01700

No, there are pins on each controller with the pin name if LDO. Need to measure each such pin for a voltage.

[Instafixx]

Re: Macbook A2141 820-01700

No, there are pins on each controller with the pin name if LDO. Need to measure each such pin for a voltage.

Sorry but i am unable to understand. Can you please guide?

[mon2]

Re: Macbook A2141 820-01700

https://boards.rossmanngroup.com/thr...-solved.62923/

In diode mode testing, remove all power. Meter in diode mode.

Red meter probe, yes red, to ground.
Black meter probe to point to test.

Post your updates.

[Instafixx]

Re: Macbook A2141 820-01700

https://boards.rossmanngroup.com/thr...-solved.62923/

In diode mode testing, remove all power. Meter in diode mode.

Red meter probe, yes red, to ground.
Black meter probe to point to test.

Post your updates.

(Meter Set to 2k Scale)

PP1V5_UPC_TA_LDO_CORE is 450 (CB304)
PP3V3_UPC_TA_LDO is 450 (CB308 The Cap is Missing)

PP1V5_UPC_TB_LDO_CORE is 450 (CB404 This Came Off When Testing)
PP3V3_UPC_TB_LDO is 450 (CB408 The Cap is Missing)

PP1V5_UPC_XA_LDO_CORE is 450 (C3104)
PP3V3_UPC_XA_LDO is 350 (C3108)

PP1V5_UPC_XB_LDO_CORE is 450 (C3204)
PP3V3_UPC_XB_LDO is 350 (C3208)


THE TA AND TB LOCATION IS THE AFFECTED AREA WITH MANY CAPS MISSING AS MENTIONED ABOVE ALSO.

[piernov]

Re: Macbook A2141 820-01700

SSD circuit (2V5 rail buck converter and SSD ICs) will most likely be damaged as it is so common after liquid damage on A2141

[Instafixx]

Re: Macbook A2141 820-01700

SSD circuit (2V5 rail buck converter and SSD ICs) will most likely be damaged as it is so common after liquid damage on A2141

How to resolve this?
PP2V5_NAND_SSD1 is at 0 Volts.

[mon2]

Re: Macbook A2141 820-01700

Focus on U9080.

What is the voltage to ground of SSD1_VR_P2V5_EN_R ?

You can measure @ R9098. This is the ENable pin for the missing voltage rail needed by the SSD.

If this EN pin is a logic '1' = high, then U9080 is being requested to turn ON but due to the possible liquid damage, the output is not present.

So this will mean that U9080 needs to be replaced.

With no power, do measure the resistance to ground of PP2V5_NAND_SSD1.

[Instafixx]

Re: Macbook A2141 820-01700

Focus on U9080.

What is the voltage to ground of SSD1_VR_P2V5_EN_R ?

You can measure @ R9098. This is the ENable pin for the missing voltage rail needed by the SSD.

If this EN pin is a logic '1' = high, then U9080 is being requested to turn ON but due to the possible liquid damage, the output is not present.

So this will mean that U9080 needs to be replaced.

With no power, do measure the resistance to ground of PP2V5_NAND_SSD1.

SSD1_VR_P2V5_EN_R at R9098 is 0 Volts


Resistance at PP2V5_NAND_SSD1 is 70.
(Meter set to lowest scale i.e 200)