Can you confirm how these measurements were taken ?
Meter in DC volts scale (20v or higher is ok).
Red meter probe to source pins (1-2-3) ; pick one
Black meter probe to ground (shield ground is ok)
Then review the voltage on this pin.
Repeat for the DRAIN pins (5-6-7-8).
Repeat for the GATE pin (4).
For each case, black meter probe to ground.
Then the same check for the next mosfet.
All measurements were taken with an automatic multimeter. It is a fluke tester.
I always use a 30v 10A power supply. At first the voltages were disparate since the power supply varied voltages. I already repaired it obtaining safe voltages.
With the source regulated at 19.50v, which is the input that is placed on the laptop's casing:
Mosfet 1:
1,2,3 - 19,53v
5,6,7,8 - 19,53v
8 - 25,53v
Mosfet 2:
1,2,3 - 19,53v
5,6,7,8 - 19,53v
8 - 25,53v
I understand your frustration at seeing how I don't understand or don't do things well. Please make an effort. I'm learning as I go and I'm doing my best to understand you. Thank you so much for your time.
This case lacks in a good overview and a detailed explanation of the issue.
For this reason members here were mislead to whole two pages of troubleshooting the DC-IN Circuit, although the main power rail is fine and the board works, at least till some degree.
So if you finally want to make some progress here, we need information about the resistance to GND of any coil on your board and also of voltage present at any coil WHILE plugging the charger (to not miss something again!). Write the values near the coils at the photo you have already taken of the board. Thanks.
One more thing: So does the 3.3V at the coil disappear even without pressing the power button? If it does not disappear, then repeat the voltage measurement WHILE the button is pressed.
This case lacks in a good overview and a detailed explanation of the issue.
For this reason members here were mislead to whole two pages of troubleshooting the DC-IN Circuit, although the main power rail is fine and the board works, at least till some degree.
So if you finally want to make some progress here, we need information about the resistance to GND of any coil on your board and also of voltage present at any coil WHILE plugging the charger (to not miss something again!). Write the values near the coils at the photo you have already taken of the board. Thanks.
One more thing: So does the 3.3V at the coil disappear even without pressing the power button? If it does not disappear, then repeat the voltage measurement WHILE the button is pressed.
First of all, thanks for your interest. I will try to be as precise as possible:
All coil voltages are measured by plugging the power supply into each of them.
The 3.3v coil falls to 0v the second after plugging in the power supply, without pressing the power button in any of the cases.
The bios chip receives 3.3v and the second drops to 0v.
Understand. Okay, resistances looking fine so far. I'm a bit worried about the two coils with 1.5Ohms to GND but can be fine. So there is no clear reason why it does shutdown after a short while.
Does the 3.3V coil (and maybe other voltages) come up again while you press the power button?
Charger is known good and of correct wattage?
Understand. Okay, resistances looking fine so far. I'm a bit worried about the two coils with 1.5Ohms to GND but can be fine. So there is no clear reason why it does shutdown after a short while.
Does the 3.3V coil (and maybe other voltages) come up again while you press the power button?
Charger is known good and of correct wattage?
If I press the power button nothing happens. Only the power light comes on for an instant. This light never comes on when I plug in the power supply. I don't use a power supply. I only use a 30V and 10A laboratory source. That would be enough amperage to start it.
Well, if ANYTHING happens after pressing the power button you should proceed by measuring all coils again while pressing the button. Might give a hint then where it is stuck.
Edit: Question about the charger wasn't answered. Please clarify. Charger is a very important thing on HP notebooks.
Well, if ANYTHING happens after pressing the power button you should proceed by measuring all coils again while pressing the button. Might give a hint then where it is stuck.
In the coils there is no change in the voltages. There is only a voltage drop in the connector of the power led and it charges for an instant returning to its 5v state.
Edit: Question about the charger wasn't answered. Please clarify. Charger is a very important thing on HP notebooks.
I don't use a charger from HP. I don't have a charger for this laptop. I use a laboratory source.
With a tip which cover the the Adapter detection of the board? Picture of how it is connected?
Understood. I know what AD_ID means. My ignorance was to blame. I'll buy the charger and post the result. I have a charger but it's from an Alienware. I thought that since it didn't work with the hp, the laptop would be bad.Thanks for opening my eyes
I have already bought the original charger and I am waiting to receive it. Now I need to know the values of three capacitors that I destroyed by clumsiness when desoldering an IC and a mosfet. Could someone help me?
I have already bought the original charger and I am waiting to receive it. Now I need to know the values of three capacitors that I destroyed by clumsiness when desoldering an IC and a mosfet. Could someone help me?
If I look at the datasheet of the bac(sy8288), those capacitors go to pin 15 and 14. I can assume that the one on 15 is 4.7u-6.3v but the one on 14 would be 1000p-25v?
In the BQ738h it is more evident that it goes to pins 1 and 2, being the capacitor 0.1u-25v. Am I totally confused or did I deduce the problem correctly?
I have already bought the original charger and I am waiting to receive it. Now I need to know the values of three capacitors that I destroyed by clumsiness when desoldering an IC and a mosfet. Could someone help me?
If I look at the datasheet of the bac(sy8288), those capacitors go to pin 15 and 14. I can assume that the one on 15 is 4.7u-6.3v but the one on 14 would be 1000p-25v?
In the BQ738h it is more evident that it goes to pins 1 and 2, being the capacitor 0.1u-25v. Am I totally confused or did I deduce the problem correctly?
I already have the original charger and if you could confirm the above, I would be ready to check the laptop.
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