820-3437 - does not recognize charger

Palhano

Member
Very complicated Mac.

It arrived without recognizing MagSafe and cooler fired. I only discovered the oxidized U5800. I cleaned everything and replaced it, the Mac worked perfectly for 2 days and stopped recognizing the MagSafe (no LED and the system does not recognize the connected MagSafe). I took it apart to test, it worked again. A day passed, it stopped recognizing Magsafe, when I disconnect the battery, it recognizes MagSafe again.

Note: When it was working, recognizing MagSafe, whenever I connected MagSafe, the Mac would turn on.

I changed the DC board and cable, the battery and it didn't solve the problem. Using original MagSafe.

I'm waiting for it to stop working again to check voltages.

With it working:
PP3V42_G3H - 3.4v
PPBUS_G3H - 8.6v
ISL6259 pins 17.18 - 4ohms, 27.28 - 20ohms

Maybe the bad ISL6259?
 

Palhano

Member
I tried reballing and changed the SMC. It didn't solve it.

As long as there is charge in the battery, it turns on and works. But it doesn't recognize the charger.
 

2informaticos

Administrator
Staff member
I get confused with a 2936 I was working with on my desk.

Do you get amber light on the Magsafe?
Did you try SMC bypass mode?

Check resistance (ohm scale) between pins 17/18 and 27/28 of U7100.
 

Palhano

Member
When it doesn't recognize the charger, I don't have any light. Battery icon on MacOs also shows charger connected.

I had already tested the ISL, pins 17.18 - 4ohms, 27.28 - 20ohms

The Mac turns on, do I test it in SMC bypass mode to check if it charges the battery?
 

Palhano

Member
The problem returned.

I thought something was crazy. It doesn't recognize just MagSafe 45w. I tested it with two different and original chargers, it doesn't charge the battery and doesn't even light the LED.
When I put the MagSafe 85w (original), it charges the battery and lights up.
I replaced the DC board and the flex, same problem.

Any tips?
 

Palhano

Member
Another crazy detail.

Without the battery, the 45w charger has an LED and turns on the board. Tried changing the battery, same problem.
 

2informaticos

Administrator
Staff member
Check ohm resistance between pins 17/18 and 27/28 of U7100.

Start in diagnostic mode with 45W charger (no battery) and see what errors pop up.
 

Palhano

Member
pins 17.18 - 4.4ohms, 27.28 - 21ohms

In diagnostic mode, the only error that appears is that there is no battery. Does this model still have ASD?
 

Palhano

Member
Without battery with 45w
PPBus - 8.56v
PP3V42 - 3.42v

With 45w battery
PPBus - 8.16v
PP3V42 - 3.42v

With 85w battery
PPBus - 8.26v
PP3V42 - 3.42v

I ran the ASD without the battery, it gave an error in the battery sensors
Sensor - Temperature (TBOT) -- Battery Thermal Diode 0 (test 1)
Sensor - Temperature (TB1T) -- Battery Thermal Diode 1 (test 1)
Sensor - Temperature (TB2T) -- Battery Thermal Diode 2 (test 1)

Is it because it has no battery?
 

Palhano

Member
The problem only happens with the board, dc and battery.

I noticed that the entire PPDCIN_G3H line drops the voltage, it drops even when connected to the 45w charger. I replaced the Q7180, but it didn't solve the problem.

It looks like a leaky component. But I can't find it.
 
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