820-01521 liquid damaged

drmacbookth

New member
Hi, I have an Air with liquid damage around Type-C ports. CD3215 (5V 0A ) had a short on one of the 3.3v lines and one got a bit warm, after replacement shorts are gone. Also no short on any of the big coils. Now I get 5.15v 0.02A and then switching to 5.02v and 0.26A and staying there. PPBUS is 12.29V, should be 12.6? What should I check next?
 

drmacbookth

New member
Note there was some corrosion on R3103, R3105 and R3109, i replaced them no shorts and resistance is correct, no change in charging
 

2informaticos

Administrator
Staff member
Each CD3215 must get 1V1 LDO, only when the charger is connected to corresponding port.
The other 3 LDOs are always present.

BTW, LDOs are clearly visible inside chip pin notations!
 

drmacbookth

New member
OK, I measured as follows with charger connected:



U3100 (charger connected)

C3108 = 3.28
C3106 = 1.81
C3105 = 1.8
C3104 = 1.11

U3200 (charger connected)

C3208 = 3.3
C3206 = 1.8
C3205 = 1.8
C3204 = 1.1

Seems all LDO lines are OK. I have 3.29 on both CD3215 PP3v3_G3H_RTC lines as well as 5v incoming. Would you suggest try other CD3215's or are there other voltages that need to be present to create 20v?
 

drmacbookth

New member
The SLPS2R signals are there and so are the Awake: 1.1, 1.8, 3.3. I noticed the T2 chip getting hotter then the rest of the board by 5 degrees, is this normal or could it be T2 issues?
 
Top