Apple Macbook Pro / 5.09v 0.41a / U3100 Damaged / Board 820 - 01041 - 07 /

[zeydullak]

Hello,

We have a Apple Macbook pro that had a damaged U3100, we replaced it, the board is now using 5.09v and 0,41a. checking under our thermal camera we see the T2 chip warming up along with a few other elemnets.

What else could be causing the problem and what should we start by looking at first.

Regards,
Zeydulla,

 

[2informaticos]

All the ports have the same behavior?

Compare diode mode readings on LDO lines of all CD3215 chips.
Just in case, reflash U2890; make backup first.

 

[zeydullak]

All the ports have the same behavior ranging from .41-.43. I did regular diode mode testing.

U2890 is holding the ROM firmware? I can read it but I dont have another copy of it to reflash. Do you have one?

U3100
PP1v8_UPC_XA_LDOA --> 1.3
PP3V3_UPC_XA_LDO --> open
PP1V1_UPC_XA_LDO_BMC --> open

U3200
PP1V8_UPC_XB_LDOD --> 1.34
PP1V1_UPC_XB_LDO_BMC --> open
PP3V3_UPC_XB_LDO --> open

UB300
PP1V8_UPC_TA_LDOD --> 1.38
PP1V1_UPC_TA_LDO_BMC --> open
PP3V3_UPC_TA_LDO --> 1.71

UB400
PP1V8_UPC_TB_LDOD --> 1.3
PP1V1_UPC_TB_LDO_BMC --> open
PP3V3_UPC_TB_LDO --> open

 

[2informaticos]

Recheck all in correct way; red probe on ground!
BTW, each chip has two 1V8 LDOs.

A1990 820-01041-A U2890 .bin

drive.google.com

I can't confirm this file 100%, being downloaded from vinafix.

 

[zeydullak]

U3100
PP1V8_UPC_XA_LDOD --> .4880
PP1V1_UPC_XA_LDO_BMC --> .5167
PP3V3_UPC_XA_LDO --> .5151
PP1V8_UPC_XA_LDOA --> .5262

U3200
PP1V8_UPC_XB_LDOD --> .4941
PP1V1_UPC_XB_LDO_BMC --> .5264
PP3V3_UPC_XB_LDO --> .5265
PP1V8_UPC_XB_LDOA --> .5340

UB300
PP1V8_UPC_TA_LDOD -->.4946
PP1V1_UPC_TA_LDO_BMC --> .5202
PP3V3_UPC_TA_LDO --> ,5179
PP1V8_UPC_TA_LDOA --> .4304

UB400
PP1V8_UPC_TB_LDOD --> .4965
PP1V1_UPC_TB_LDO_BMC -->.5250
PP3V3_UPC_TB_LDO --> .5150
PP1V8_UPC_TB_LDOA --> .5343

 

[2informaticos]

I don't see big differences.

Check voltages on the powered CD3215 port.