tcampbell34
Member
Hello. I have a 820-01700 that has no liquid damage, but was not turning on. I was getting 20v and amps fluctuating up to .700ma and then back down to 0.03a. The ports on the right side of the mac did not work at all and gave me 0v on my meter. I checked those ports and found a short on USBC_TB_CC1, USBC_TA_CC1, USBC_TA_CC2. I replaced UB300/400 with new chips I got on eBay and then I was getting 5v 0.27a on all 4 ports. I decided to try it with a charged battery and got it to turn on with the battery connected and it boots to the OS, but charger is not detected. Amp meter shows 20v 0.03a on all 4 ports when the board is on and booted with the battery connected. UPC_I2C_INT_L is always 0v, which I think is why the charger is not being detected. It is 1.8v on a good board. R5246 is good. Doing more research I found this https://logi.wiki/index.php/CD3217_and_T2_Power_on_Sequence#820-001700_CD3217_Compatibility_issues which seems to indicated that some CD3217 chips are not compatible with this board. I then tried to take good 2 CD3217 chips from a 2019 820-01598 donor board and reballed them and replaced UB300/400 again, but I still have the same issue. I even tried a T2 firmware restore and it completed successfully, but did not fix the issue. What should I check next?