820-00165 A1466 MacBook Air missing PPBUS_G3H

[techstar85]

Hi guys,

I'm working on an 820-00165 which had encountered fluid damage, mainly around U7100. Replaced U7100 and a couple of resistors that had corroded off the board, flux and boiled the crap away from a couple of other areas which do not appear to have any lasting damage.

Initially had no green light, diagnosed as a failed D7012, now have green light on the magsafe, but still not getting PPBUS_G3H and no fan spin. No short on PPBUS and fuse is fine.

PP5V_S5 is only 0.8v and PPDC_IN is 16.4v. Tried to decipher the scematic to work out where the rail is being pulled down but getting stuck

Can anyone point me in the right direction?

[mon2]

Re: 820-00165 A1466 MacBook Air missing PPBUS_G3H

hi.

1) voltage @ D7005, pins 1, 2 and 3 ? (PPVIN_G3H_P3V42G3H)

2) voltage @ R7095, pin # 2 (P3V42G3H_FB) ?

3) voltage @ PP3V42_G3H = L7095, pin # 2 ?

4) Power down, meter in resistance mode.

Black lead to ground; red lead on L7095, pin # 1 - reading in ohms ?

Black lead to ground; red lead on L7095, pin # 2 - reading in ohms ?

5) voltage of PPDCIN_G3H ?

6) voltage of PPDCIN_G3H_INRUSH ?

7) voltage of CHGR_UGATE ?

8) voltage of CHGR_LGATE ?

9) voltage of PP5V1_CHGR_VDD ? This rail powers U7100 which creates the PPBUS_G3H voltage.

[techstar85]

Re: 820-00165 A1466 MacBook Air missing PPBUS_G3H

Hi mon2, thanks for responding:

1. pin1 = 0v , pin2 = 16.3v, pin3= 16.0v

2. 1.24v

3. 3.38v

4. Pin1= 50k but appears to jump up and down between 48-52k
Pin2 = 87.6k

5. 16.44v

6. 0v

7. 0v

8. 0v

9. 0v

I had identified that PP5V1 wasn't present (therefore U7100 most likely not powering up) but thats where I got stumped by trying to interpret the schematic - I'm still learning!

[mon2]

Re: 820-00165 A1466 MacBook Air missing PPBUS_G3H

1) voltage @ PPDCIN_G3H_ISOL ?

2) voltage @ CHGR_ACIN ?

3) voltage @ PPCHGR_DCIN_D_R ?

4) voltage @ CHGR_DCIN ?

Also, my bearings for U7100 may be incorrect. This regulator is powered, I believe through CHGR_DCIN, pin # 2.

This regulator, U7100 from Intersil (now Renesas) does not have public datasheets available for our review. However, based on assorted youtube videos, most likely U7100 is damaged but do post the above details to rule out any support component causing this issue.

U7100 = ISL6259HRTZ


https://www.aliexpress.com/premium/I...psort=1&page=1

[techstar85]

Re: 820-00165 A1466 MacBook Air missing PPBUS_G3H

1. 16.44v

2. 4.32v

3. 16.41v

4. 16.41v

U7100 has already been replaced with new (not from donor) prior to onewire circuit being fixed to restore green light