emachines d725 cannot turn on with power button

[String2016]

hi everyone i need help on this emachines d725 board code:HM40-MV 08242-1M 48.4BW01.01M cannot turn on on power button but when short on pin7 on power button laptop is on and boots fine i noticed there is on 3.3v on power button but have 3.3v on pin7 pn the power button connector on motherboard.anyone can help on this please i have attached the image

[mielta]

Re: emachines d725 cannot turn on with power button

Hi
Please mesure on pin 8 if there is 3,3v
when yes make a short to ground for a second and see if the laptop starts

[meritosari]

Re: emachines d725 cannot turn on with power button

Hi
Please mesure on pin 8 if there is 3,3v
when yes make a short to ground for a second and see if the laptop starts

KBC_PWRBTN#_1====pin 9 of PowerCN1

[String2016]

Re: emachines d725 cannot turn on with power button

@meritosari thanks for the response i can turn on the laptop if i short pin 7 and 8 but when i press power button cannot turn on. there is no 3.3v on power button switch but on pin 7 and 8 there is 3.3v.where should i make jumper wire for this?

[raajkumar]

Re: emachines d725 cannot turn on with power button

Yes you can use a jumper wire on it.

[String2016]

Re: emachines d725 cannot turn on with power button

@raajkumar where to put jumper?

[raajkumar]

Re: emachines d725 cannot turn on with power button

@raajkumar where to put jumper?

Pin no.8 of the kbc to power switch 3.3v line. Before you connect it check that line is that short circuited or not if it is not short circuited you can connect it. I had the same experience on an acer laptop. I don't had schematic for that model. So I used this trick on that it was successfully done.

[String2016]

Re: emachines d725 cannot turn on with power button

ok thanks i will try that

[String2016]

Re: emachines d725 cannot turn on with power button

i already tried make jumper on pin 8 of kbc to switch but still the same issue cannot turn on by power switch but when i short pin 7 and pin 8 on cn1 laptop turns on and boots fine

[String2016]

Re: emachines d725 cannot turn on with power button

anyone help on this please could it be power switch problem?

[raajkumar]

Re: emachines d725 cannot turn on with power button

Do a test continuity of that ribbon cable between mb and power switch board. Check the switch also with ohm meter.

[String2016]

Re: emachines d725 cannot turn on with power button

i test the ribbon continuity is good but when i plugged in to power button pin 1 on the board and pin 1 2 3 on the power switch have continuity

[HarryPK]

Re: emachines d725 cannot turn on with power button

change the power botton board

[raajkumar]

Re: emachines d725 cannot turn on with power button

i test the ribbon continuity is good but when i plugged in to power button pin 1 on the board and pin 1 2 3 on the power switch have continuity

Check if there any small capacitors and transistors or led on that switch board top or bottom side. Sometimes if there anything short circuit, even switches also short circuit it also makes these kind of problems.

[String2016]

Re: emachines d725 cannot turn on with power button

there is no capacitor or small transistor on the power board but there is led light i checked also pin 123 beeping to ground on the power board and when checked with continuity test the led light the one on the power switch button when i touch both sides with probe it lights up with orange light and the same with led number 3 when i touch it lights orange.but the other led light not it has 6 led light on the power board

[raajkumar]

Re: emachines d725 cannot turn on with power button

So think simple. Get two wires from pn7 and pin8 of that board. Disconect previous lines for power switch and connect that two wires with power switches two pins. Thats all. Be happy.

[String2016]

Re: emachines d725 cannot turn on with power button

thanks you mean from pin 7 and pin 8 on the motherboard to power button switch?

[meritosari]

Re: emachines d725 cannot turn on with power button

thanks you mean from pin 7 and pin 8 on the motherboard to power button switch?

- Read the schematic if you want to repair motherboard laptop/computer, since all part on mobo was Surface Mount Devices type. the motherboard has more 5 layer inside it. Wrong to take line can be causing other problem.
- Always make habbit to type message with coma and dot in your sentence.
- This mobo was eaten by age, so many components on it could be has change value or leakage.
- I think that make jumper to shorted pin 7,8 and 9 together at POWERCN1 only as last option if problem still persist. (pin7=TP_LOCK_BN#_1, pin8=PWRLED#_R, pin9=KBC_PWRBTN#_1) think here...............
- Make sure you have 3V on 2 pcs triangle G1 near POWERCN1. Try short G1, and see what result. If you can switch ON, then problem on ribbon cable and sub board power button.
- I would prefer to check a few components which connected to KBC_PWRBTN#, such as RN47 and RN1, maybe "resistor network" was open or change value.

[HarryPK]

Re: emachines d725 cannot turn on with power button

- Read the schematic if you want to repair motherboard laptop/computer, since all part on mobo was Surface Mount Devices type. the motherboard has more 5 layer inside it. Wrong to take line can be causing other problem.
- Always make habbit to type message with coma and dot in your sentence.
- This mobo was eaten by age, so many components on it could be has change value or leakage.
- I think that make jumper to shorted pin 7,8 and 9 together at POWERCN1 only as last option if problem still persist. (pin7=TP_LOCK_BN#_1, pin8=PWRLED#_R, pin9=KBC_PWRBTN#_1) think here...............
- Make sure you have 3V on 2 pcs triangle G1 near POWERCN1. Try short G1, and see what result. If you can switch ON, then problem on ribbon cable and sub board power button.
- I would prefer to check a few components which connected to KBC_PWRBTN#, such as RN47 and RN1, maybe "resistor network" was open or change value.

case closed

[String2016]

Re: emachines d725 cannot turn on with power button

@meritosari thanks for the schematic the problem with this is the power board switch because as iv'e mentioned above that i can power on the laptop if i short pin 7 and pin 8 on the and near G1 on the CN1 have voltages.the problem with this is the power switch board