Macbook Pro A1502 Adaptor Shorted When Battery Attach

[ronelex]

Macbook Pro A1502 Adaptor Shorted When Battery Attach

Unit works on Battery Mode
Unit works on Adaptor Mode
But When Adaptor and Battery both attach, the charger plug overheat so much, when using PSU it draw 3A when battery is attach

Checking battery connector when adaptor only attach, J7050 PPVBAT_G3H_CONN measures 12v- 0v- 12v cycle and the mosfet driving Q7155 pin 4 measures 5v then 12v cycle

[mon2]

Re: Macbook Pro A1502 Adaptor Shorted When Battery Attach

Check to see if Q7155 is shorted.

Remove the battery and adapter.

Check the resistance between

a) SOURCE & DRAIN

b) SOURCE & GATE

c) DRAIN & GATE

[ronelex]

Re: Macbook Pro A1502 Adaptor Shorted When Battery Attach

Q7155 is shorted but when I replaced it and tried again with battery current is ok at first until it reach 3A plus again and gfound out the replaced mosfet is shorted again

[mon2]

Re: Macbook Pro A1502 Adaptor Shorted When Battery Attach

1) voltage @ CHGR_CSO_R_P ? R7151 present ?

2) voltage @ CHGR_CSO_R_N ? R7152 present ?

3) voltage @ PPVBAT_G3H_CHGR_R ?

4) voltage @ CHGR_BGATE ?

5) is the battery known good ? Perhaps the battery pack is causing the excessive drain and killing the mosfet? Can you test with another battery pack ?

Will ping Nicusor on this thread for advice - he is the author of the NLBA1 tool which is for laptop battery charging and knows this topic very well.

[ronelex]

Re: Macbook Pro A1502 Adaptor Shorted When Battery Attach

1) voltage @ CHGR_CSO_R_P ? R7151 present ? - 12.5v

2) voltage @ CHGR_CSO_R_N ? R7152 present ? - 12.5v

3) voltage @ PPVBAT_G3H_CHGR_R ? - 12v

4) voltage @ CHGR_BGATE ? 5v-12v cycle every 2 seconds i think

5 ) Battery no available but the unit is working good on battery mode, but i will look a new one to test

Thanks for the help sir

[azzidoqsc]

Re: Macbook Pro A1502 Adaptor Shorted When Battery Attach

"Unit works on Battery Mode" -> this tells us that the battery is discharging fine and the motherboard can be powered from the battery.

"Unit works on Adaptor Mode" -> this tells us that the motherboard can be powered from the AC adapter.

None of the above scenarios does test the charging path: charging block of the motherboard and charging block of the battery pack.

"But When Adaptor and Battery both attach" -> this scenario uses the charging modules from both motherboard and battery. The battery communicates with the motherboard and informs it what is the charging current. The charging current is requested by the battery and assured by the motherboard. The charging current is adjustable based on the charging level and cells voltage. If it is not in pre charging mode or in constant voltage mode the requested charging current could be even 6Amps, depending on the battery chemistry, cells configuration, etc. So, 3Amps should not be a big current.

Where did you measure 3Amps ?
What is the wattage of the AC adapter ? Is it Genuine ?
Does the battery belong to the motherboard ?

I have seen a wrong behavior in one Dell battery where the instant current was reported 4 times smaller than the real current. It was something wrong with the current sens resistor inside the battery. The NLBA1 device was reaching charging current 3Amps but the battery was reporting 700mA.

[ronelex]

Re: Macbook Pro A1502 Adaptor Shorted When Battery Attach

Im using a Power bench to test, because the charger I used is already damaged, first use it charge normally until I notice it lost the light and the plug overheats so much which I think kills the charger. So I test the unit using the power bench and It draws a lot when charging but I dont know if its normal because I only tried A1466 model, I dont have data on this model