820-00165 Random green light on charger

[ahoonid]

Thanks for your input reformatt.

I checked voltage on R7012 with only the battery connected and both pins show 0v.

On D7005 with only the battery:
Pin 1: 7.66v
Pin 2: 0.09v
Pin 3: 7.47v

On R7180 which, I initially got 8.40v but it dropped a little every time I connected the multimeter probes and finally stopped at 7.38v.

So is it the D7005 that's leaking via pin 2?

[mon2]

Test this way...remove all power. Meter in DIODE mode. Short your meter probes and the meter should tone beep.

With no power to the board; no battery to the board - connect the RED meter probe onto pin # 1 (anode) of this dual common cathode diode. BLACK meter probe onto pin # 3 (cathode).

You should have a voltage reading. What is this value?

Now reverse the meter leads and the diode should block. Confirm this.

Repeat with pins 2 & 3 on this same dual diode. So in diode mode, the diode should conduct in one direction and block in the other. Be sure this part is behaving correctly otherwise it is defective and should be replaced.

[reformatt]

Thanks for your input reformatt.

I checked voltage on R7012 with only the battery connected and both pins show 0v.

On D7005 with only the battery:
Pin 1: 7.66v
Pin 2: 0.09v
Pin 3: 7.47v

On R7180 which, I initially got 8.40v but it dropped a little every time I connected the multimeter probes and finally stopped at 7.38v.

So is it the D7005 that's leaking via pin 2?

No. Looks ok to me. If you have your ~18V when the charger is plugged in at PPDCIN_G3H (even during your fault condition), then that side of it is ok.

The LED on the charger going out is most often the magsafe connector itself or the one on the charger. It's the centre pin of the connector and often jiggling the connector often resolves it. AFAIK, there aren't any 'new' LIO boards in the market, they are all 2nd hand. Use of the aftermarket chargers can damage these connectors due to the sparking when plugging in. I always have a genuine charger around to use as a sanity check for these kinds or problems. Anything you get on eBay, Aliexpress are knockoffs BTW.

Also pay close attention to the connector for the LIO board (J9500), either the pins internally or at the base of the connector. Very common to have these liquid damaged.

[ahoonid]

Test this way...remove all power. Meter in DIODE mode. Short your meter probes and the meter should tone beep.

With no power to the board; no battery to the board - connect the RED meter probe onto pin # 1 (anode) of this dual common cathode diode. BLACK meter probe onto pin # 3 (cathode).

You should have a voltage reading. What is this value?

Now reverse the meter leads and the diode should block. Confirm this.

Repeat with pins 2 & 3 on this same dual diode. So in diode mode, the diode should conduct in one direction and block in the other. Be sure this part is behaving correctly otherwise it is defective and should be replaced.

Red on 1 Black on 3: Beeps once and shows .197v
Reverse: No beep and shows 1.930v

Red on 2 Black on 3: Beeps once and shows .199v
Reverse: No beep and shows .0Lv

Does it confirm the issue must be here?

[ahoonid]

No. Looks ok to me. If you have your ~18V when the charger is plugged in at PPDCIN_G3H (even during your fault condition), then that side of it is ok.

The LED on the charger going out is most often the magsafe connector itself or the one on the charger. It's the centre pin of the connector and often jiggling the connector often resolves it. AFAIK, there aren't any 'new' LIO boards in the market, they are all 2nd hand. Use of the aftermarket chargers can damage these connectors due to the sparking when plugging in. I always have a genuine charger around to use as a sanity check for these kinds or problems. Anything you get on eBay, Aliexpress are knockoffs BTW.

Also pay close attention to the connector for the LIO board (J9500), either the pins internally or at the base of the connector. Very common to have these liquid damaged.

Yes I have the 18v indeed. I am dead sure about my magsafe being genuine. The magsafe cabe connected to my PSU is also geniune. They have no issue with working devices!
As for the LIO, I tested an original and working one from another device and still got the same issue. connectors on both side seem very clean.

One thing I noticed after leaving the device for a few days was that the magsafe light from the original charger wouldn't turn on at all. The system information was recognizing it as connected but in front of charging was written No. I waited for a few minutes and even did an smc reset but still got the same no light on the magsafe.
Then I connected it to my PSU magsafe and after a 10-15 seconds (fluctuating between 30 to 60 and 70mA and then to 1A and dropping to 60 and 40mA), the light came on and cosequently the original magsafe started to turn on as well and charge the device!

[ahoonid]

Test this way...remove all power. Meter in DIODE mode. Short your meter probes and the meter should tone beep.

With no power to the board; no battery to the board - connect the RED meter probe onto pin # 1 (anode) of this dual common cathode diode. BLACK meter probe onto pin # 3 (cathode).

You should have a voltage reading. What is this value?

Now reverse the meter leads and the diode should block. Confirm this.

Repeat with pins 2 & 3 on this same dual diode. So in diode mode, the diode should conduct in one direction and block in the other. Be sure this part is behaving correctly otherwise it is defective and should be replaced.

Do you think I should go ahead mon2?

[mon2]

Disconnect the battery. Attach the power adapter only. Measure the voltage to ground on each leg of D7005. Post each measurement.

[ahoonid]

Disconnect the battery. Attach the power adapter only. Measure the voltage to ground on each leg of D7005. Post each measurement.

1: 8.60
2: 16.49
3: 16.28

I did this measutments with the MLB inside the laptop only disconeecting the battery. The magsafe light was on for a minute, I took the measurments, and then the light turned off! The laptop is still up and running and system information confirms the charger is connected!
Charger is original 65w magsafe.

I get the same values on D7005 with the charger light out.

[mon2]

After the led on MagSafe turns off, what is the voltage of the 3v42 rail?

[ahoonid]

After the led on MagSafe turns off, what is the voltage of the 3v42 rail?

It is 3.42v surprisingly!
tested from R5127 and C5127 and the testpad nearby.

[mon2]

Review this article that was the first breakthrough one for this topic:

http://www.righto.com/2013/06/teardo...gsafe.html?m=1

review the voltage of the adapter sense pin.

Do you have an arduino?

[mon2]

Magsafe troubleshooting - LogiWiki

[ahoonid]

Magsafe troubleshooting - LogiWiki

Thanks for all your inputs and feedback mon2. I finally fixed it. Unfortunately it was a faulty io board all along!! My spare io seemed to have the same problem and I only found out by chance when I tried the board inside another laptop! It was never the magsafe itself as I tried it with many other laptops. Probably something faulty with the one wire circuit on the io.

Appreciate your help anyways 👌

[mon2]

Yes, LIO board was addressed in post # 4. Glad you figured it out. Appreciate the follow up for future readers.

[ahoonid]

Yes, LIO board was addressed in post # 4. Glad you figured it out. Appreciate the follow up for future readers.

Yes indeed. But out of bad luck of having another bad io board, I completely disregarded any possible issues with io 😅 my bad anyways. Goes to show how important it is to not just double but triple check stuff sometimes!
Cheers mate.