820-00239-A 5V

[tipoti]

hello,

820-00239 won't turn on after fall

5v was drawing 265 amps. CB408 was showing short circuit when I checked. I disassembled the CB408. No more short circuits. but keweisi opens and closes. it shows 5v

 

[2informaticos]

Probably damaged USB-C connector.
Did you test the board out of shell, using another connector?

 

[tipoti]

same response on all connectors

 

[2informaticos]

I meant replacing (supposed) damaged connector.

Check voltage and diode mode to ground readings on LDOs of all CD3215 chips.

 

[tipoti]

Voltages come and go as the device turns off and on.
PP3V3_UPC_TB_LDO = 3,3 volt
PP1V8_UPC_TB_LDOA =1,8 Volt
PP1V8_UPC_TB_LDOD = 1,8 Volt
PP1V1_UPC_TB_LDO_BMC = No voltage

 

[tipoti]

No shorts except CB408. no field with low ohms

 

[tipoti]

only 1 entry does not turn off. Restarts on other 3 entries

5v restart.mp4

Görüntüle ve Yandex Disk'ten indir

disk.yandex.com.tr

 

[2informaticos]

You must get same behavior on all USB-C ports.

"diode mode to ground readings on LDOs of all CD3215 chips."
You don't need power for that...

 

[tipoti]

I said there is no short circuit
CB408 was shorted. So could the UB400 be faulty?

U3200
PP1V1_UPC_XB_LDO_BMC = 0.486
PP1V8_UPC_XB_LDOD = 0.459
PP1V8_UPC_XB_LDOA = 0.492
PP3V3_UPC_XB_LDO =0.509

U3100
PP3V3_UPC_XA_LDO =0.509
PP1V8_UPC_XA_LDOA =0.483
PP1V8_UPC_XA_LDOD =0.464
PP1V1_UPC_XA_LDO_BMC = 0.492

ub300
PP3V3_UPC_TA_LDO =0.509
PP1V8_UPC_TA_LDOA =0.502
PP1V8_UPC_TA_LDOD =0.465
PP1V1_UPC_TA_LDO_BMC =0.492

ub400
PP3V3_UPC_TB_LDO =0.509
PP1V8_UPC_TB_LDOA =0.492
PP1V8_UPC_TB_LDOD=0.459
PP1V1_UPC_TB_LDO_BMC = 0.483

 

[2informaticos]

"only 1 entry does not turn off"
Is that UB400 port?

Check which port gets 1V1 LDO.
Remember, this voltage must appear only on the powered port.

 

[tipoti]

5v restart.mp4

Görüntüle ve Yandex Disk'ten indir

disk.yandex.com.tr

I posted a video in this link

 

[tipoti]

only ub300 does not turn off. and it outputs a constant 1.1 volts.
PP1V1_UPC_TA_LDO_BMC

others show 1.1 volts. but voltage comes and goes as it turns on and off

 

[2informaticos]

You may have a problem on that port (UB400).
May be caused by other components, related with the USB-C connector, not UB400 itself.

Board tries to start with both charger and battery connected?

You can check diode mode on all USB-C connector pins, or use some fast tester (S-UEM2).

https://es.aliexpress.com/item/1005004895035481.html?spm=a2g0o.productlist.main.9.5f19dgz6dgz6fb&algo_pvid=7ce2b6b4-75c6-47e7-9e29-788b72fbd699&aem_p4p_detail=202212150735444695623779732030003412462&algo_exp_id=7ce2b6b4-75c6-47e7-9e29-788b72fbd699-4&pdp_ext_f=%7B%22sku_id%22%3A%2212000030927940806%22%7D&pdp_npi=2%40dis%21EUR%21231.21%21231.21%21%21%21%21%21%402100baf316711185447112515d07cb%2112000030927940806%21sea&curPageLogUid=MnYZ1fqS2m4O&ad_pvid=202212150735444695623779732030003412462_1&ad_pvid=202212150735444695623779732030003412462_1

 

[tipoti]

When I check the cb309 in diode mode on another motherboard, it shows 0.502, but I can't get any value in the same part on this motherboard. Do I need to replace the UB300?

 

[2informaticos]

You should get same value as CB409 and other caps connected to SS pin of CD3215 chips.
OL reading means broken trace/solder.