820-2796 no fan

arnonabuurs

New member
Hi, I have a mac air 11 inch with no obvious liquid spil but many probe points look discolored from corrosion. Smoke was coming out of Q7260 and U7201 was frying so I replace both. Now I have a green light on the charger, no orange. I do have orange when i connect a battery, not sure how these old ones work with regards to one wire circuit. Measure the following:

PPBUS_G3H 8.39
PP3V42_G3H 3.4v
PP3V3_S5 3.3v
PP5V_S5_LDO 5v
PP5V_S3 0v

U6100 looks very clean, gets 3.3v in.

U7201
Pin 21 P3V3S5_EN 3.48v
Pin 4 P5VS3_EN 0.204v
Pin 23 VIN 8.39v
pin 12 SMC_PM_G2_EN 3.39v
Pin 25 SW2 3.31
Pin 32 SW1 0v

Resistors on S3 Rail Enables measure OK. PM_SLP_S4_L = 0.204

Any suggestions please?
 

dukefawks

Administrator
Q7260 probably shorted and made the 3V rail go high. Very good chance there is major damage to anything on the 3V rail. This board is not worth wasting time on.
 
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