dell n5010 3.3v ,5v run problem

[menshawy]

hi
dell n5010 power on without 3.3v ,5v run
u4201
D +5V_ALW 5V OK
S +5V_RUN 1.5V
G 3V
U 4202
D +3V_ALW 3V OK
S +3V_RUN 1.2V
G 3V
i think problem in PS_S3CNTRL
because r4207 pin1 3.36v ok but pin2 0v
q4202 pin2 3.3v ok
pin3 3v
pin5,6 0v
i change q4202
and pq5003 and q1801

help please

[stingerchamp]

Re: dell n5010 3.3v ,5v run problem

U4201 simple n channel mosfet
RDS 18.5 mohm

If you look at schematic unless there is high voltage at gate required to switch on and generate 5vrun with fixed current peak

C203 status ,check RDS for u4201, c4201 status
5v run enable is not coming higher at gate u4201

3.3V_RUN_ENABLE also not coming sufficient at ,u4202

Hmm nice observations r4207 check ohms increase or not

[mcplslg123]

Re: dell n5010 3.3v ,5v run problem

Check PD4601/4602. Most likely one of them is faulty

[menshawy]

Re: dell n5010 3.3v ,5v run problem

U4201 simple n channel mosfet
RDS 18.5 mohm

If you look at schematic unless there is high voltage at gate required to switch on and generate 5vrun with fixed current peak

C203 status ,check RDS for u4201, c4201 status
5v run enable is not coming higher at gate u4201

3.3V_RUN_ENABLE also not coming sufficient at ,u4202

Hmm nice observations r4207 check ohms increase or not

thanks for replay
i checked u4201 ,u4202 and changed them
r4207 is 100kohm ok

[menshawy]

Re: dell n5010 3.3v ,5v run problem

Check PD4601/4602. Most likely one of them is faulty

thanks for replay
i checked PD4601 ,PD4602 and changed them with no success

[stingerchamp]

Re: dell n5010 3.3v ,5v run problem

Let's start measuring signal levels

Vgs must be high for n channel mosfet u4201

What is voltage on r4204 both side
C4201 voltage at pin 1

R4205 voltage on both sides
It should be +15v always

Slp_s3#
1.5vsus available?
+V_DDR_REF(0.9V) available?

[menshawy]

Re: dell n5010 3.3v ,5v run problem

Let's start measuring signal levels

Vgs must be high for n channel mosfet u4201

What is voltage on r4204 both side
C4201 voltage at pin 1

R4205 voltage on both sides
It should be +15v always

Slp_s3#
1.5vsus available?
+V_DDR_REF(0.9V) available?

r4204 pin1 3.14v
pin2 14.51v
c4201 pin 1 3.14
r4205 both sides 3.14v
slp_s3# on q4202 pin2 3.3v
1.5vsus on pl5001 1.5v
+V_DDR_REF pu5001 pin5 .75v
thanks

[stingerchamp]

Re: dell n5010 3.3v ,5v run problem

hi
dell n5010 power on without 3.3v ,5v run
u4201
D +5V_ALW 5V OK
S +5V_RUN 1.5V
G 3V
U 4202
D +3V_ALW 3V OK
S +3V_RUN 1.2V
G 3V
i think problem in PS_S3CNTRL
because r4207 pin1 3.36v ok but pin2 0v
q4202 pin2 3.3v ok
pin3 3v
pin5,6 0v
i change q4202
and pq5003 and q1801

help please

[

When power button not pressed

you will have 0 voltage at q4202 gate pin 2 and left side mosfet will remain off and you have 3v at pin 5,6
and pin 5 is gate of right side mosfet so
at pin 5 3v turn on right mosfet and 0v reach at gates of u4201 u4202 u4203

When power button pressed

3.3v at q4202 at gate pin 2 of left side mosfet
Mosfet turn on left side one
0v reach at pin 5,6
Pin 5 is gate of right side mosfet
Which turn off right side mosfet
Now 15v always comes as run enable for u4201, u,4202 and etc

15v at gate of u4201 needed for 5v run



Before power button pressed
You should have 0v at gate of u4201

After power button pressed

You have 15 v always


Problem: you have 3v at gate of u4201

[mcplslg123]

Re: dell n5010 3.3v ,5v run problem

Did you solved this?? I've same mb with exact same problem. Not Looked into it yet.

[Sametbey]

Re: dell n5010 3.3v ,5v run problem

15v is important, if you don't have 15v, +5V_RUN +3,3 V and others will not come out. PU4601 RT8206 voltage regulator may be defective. if you can't find it, the update in the figure can be applied.

[mcplslg123]

Re: dell n5010 3.3v ,5v run problem

15v is important, if you don't have 15v, +5V_RUN +3,3 V and others will not come out. PU4601 RT8206 voltage regulator may be defective. if you can't find it, the update in the figure can be applied.

Thanks for your response. +15V is present and i do understand the working principle of Q4202. Pin2 Gate is ok when powered on there is 3.3V, so logically speaking ground should reach pin6. PIn5-6 are connected together, so GND reaches pin5 making 2nd mosfet of Q4202 off-so GND from pin4 should'nt travel to pin3 and there should be 15V approx at pin3 which in turn will enable VS line transfer. AS far as theory is concerned, that's correct but despite all the correct working conditions of Q4202, i'm still getting 3V at pin3 which is wrong.

Q4202 replaced but in vain. R4207/R4204/r4205/C4201/R4211/C4207/R4227/C4210 are checked and are good as per schematic.

U4201/4202/4203 are good and checked fine as per schematic.

Does anyone else can tell me the way forward??

[piernov]

Re: dell n5010 3.3v ,5v run problem

So you have 0V on pin 5 of Q4202?
And on one side of R4204 you get 15V on the other 3V?

Try removing R4227, R4211 and R4205 to see if something after them is pulling RUN_ENABLE low (just shift them off of one pad). If it's still low you can try removing Q3905 and Q4202 and check again if RUN_ENABLE is low.

[mcplslg123]

Re: dell n5010 3.3v ,5v run problem

@piernov, yes your observation is right. I already tried removing Q4202/Q3905 before responding here. I've not tried removing the resistors R4205/4211/4227. Will do and update the forum.

[mcplslg123]

Re: dell n5010 3.3v ,5v run problem

Thanks @piernov. Problem solved. 1.5V SUS was pulling down the run voltage.