[SOLVED]MacBook Air 11" (Mid 2011) 820-3024 Runs off charger but wont charge

[crea2k]

Hi, iv got a MacBook Air 11" (Mid 2011) 820-3024 which will run fine on the charger, (it auto powers on when plugged in), but when the charger is unplugged it turns off. No green light is shown on the charger.

When the mac came to me it looked like it had sustained water damage to the dc in board as some of the components were corroded, but the motherboard itself looks fine.

Iv tried 2x different chargers and 2x different dc in boards and it still wont charge. The battery has been changed and when it had charge in it the mac would run fine off the battery alone, until it went flat, then wont charge again, the mac reports the battery percentage correctly.

I have replaced ISL6259 also and still have the same problem.

The board has had some water damage at one point, but this seems to be only on the dc in board, the rest of the motherboard appears to be fine.


Here are some voltages from around ISL6250 :

CHGR_CSI_P
14.50v

CHGR_CSI_N
14.45v

CHGR_BOOT
12.89v

CHGR_UGATE
10.95

PP5V1_CHGR_VDDP
5.05v

CHGR_CSO_N
8.36v

CHGR_CSO_P
8.36v

SMC_BC_ACOK
2.97v

CHGR_RST_L
3.3v

CHGR_VNEG_R
1.3v

CHGR_VCOMP_R
1.3v

CHGR_DCIN
14.2v

CHGR_ACIN
3.74v

CHGR_ICOMP
1.54v

CHGR_CELL
0v

CHGR_VCOMP
1.52v

CHGR_VCOMP_R
1.44v

PP3V42_G3H
3.39v

Resistors tested :

Voltage @ R7005 = 14.1v & 14.35v

Voltage @ R7080 = 14.69v & 5.57v

Voltage @ R7001 = 5.1v & 5.05v

Voltage @ R7085 = 14.62v & 5.7v

Voltage @ R5420 = 0.061v & 0.061v
Voltage @ R7020 = 14.65v

Voltage @ R7021 = 14.60v

Voltage @ R7022 = 14.60v

Voltage @ R7050 = 8.36v

Voltage @ L6995 = 8.36v (=PPBUS_G3H)



EDIT >>>>>

So iv just tested R5311 and also R5312 and im getting 85k and 88k . Im testing in circuit so im not sure if im getting some measurement problem, or if you think these two could be the problem ?,

also R5313 is 25.30k instead of 27.4k , R5314 is correct rating.

@ Q5410 - CHGR_ACOK = 2.83v
DCINVSENS_EN_L = 0v
DCIN_S5_VSENSE = 14.59v
PPDCIN_S5_VSENSE = 14.62v
PDCINVSENS_EN_L_DIV = 7.18
DCINVSENS_EN_L = 0v

 

[dukefawks]

Tried a known good inboard flat cable too? Must have light on the charger or it will never charge.

 

[crea2k]

Hi, what in board flat cable ?, the dc in board plugs straight into the motherboard, I cant see any other cables on this board ?.

 

[crea2k]

No Title

 

[dukefawks]

The flat cable that is missing, goes over the fan to the board.

 

[crea2k]

Thanks !, il take the dunce hat and go sit in the corner !, looks like it was the cable.....as in not plugged in. so it was probably the dc in board or isl chip that was faulty then as it came to me plugged in and assembled.

Its my first Mac logic board issue, so glad the last part of the puzzle was something obvious !.

il try it with the battery tomorrow, but I'm sure it'll work now as had no green light when drooord off to me.

 

[crea2k]

This is confirmed fixed, so all good . Looks like the bad dc in board fried the isl chip, and the battery was also bad, but all working now.