compaq CQ43 cant on list volt measured

[sasser]

hye all masta and guru


i got 1 laptop compaq cq43 . please refer attachment where i attach schematic for this motherboard.

1st i found mosfet on Q0902 is burn mark.the mosfet model is AO4406A then im replace with wrong mosfet AO4407 .after i on the laptop Q0901 was burned then i know i make the mistake when change wrong mosfet. p channel cant change with N channel . but im learn now that mistake

im now already change new A04406A but still no power.

im measure

Q0902 no volt on all pin
Q0901 19v on pin 5,6,7,8

the IC pwr charge TPS51123 im measure 13,14,15,16 no volt

the TPS51123 for 3v 5v i measure pin 22 got 3v pin 4 3v pin8 3v pin 9 5v pin 13 3.91v pin 16 19v pin 17 5v pin 22 5v

please help me. thanks for advance

[sasser]

Re: compaq CQ43 cant on list volt measured

Hye anybody can help me?

[ktmmotocross]

Re: compaq CQ43 cant on list volt measured

no woltage on pins 22 and 11? measure resistance to groung on this pins

[aanan]

Re: compaq CQ43 cant on list volt measured

no voltage on pins 16 measure resistance to ground on this pins & check R1011 D1004 & realated track.

[sasser]

Re: compaq CQ43 cant on list volt measured

pin 16 18.6v pin 22 5v pin 11 no volt.

[ktmmotocross]

Re: compaq CQ43 cant on list volt measured

check voltage on pins 20 and 13

[sasser]

Re: compaq CQ43 cant on list volt measured

hye ktmmotocross im measured TPS51123

pin 20 = 0V
pin 13 = 4.45v
pin 16 = 18v
pin 17 = 4.94
pin 20 = 0v

on IT8518 RSMRST no volt .

power button i got 3v and bios ic also i got 3v there.

[ktmmotocross]

Re: compaq CQ43 cant on list volt measured

what about resistance to groung on L1001?

[sasser]

Re: compaq CQ43 cant on list volt measured

L1001,L1002 & L0901 both side >1ohm

[sasser]

Re: compaq CQ43 cant on list volt measured

Anyone can help here. I dont know how to determine ic tps 51123 is damaged or still ok.

[sasser]

Re: compaq CQ43 cant on list volt measured

update info:

now im reflash bios and i see on PSU current ampere is 5.0A means short some where. mosfet at Q0906 very hot when touch with finger. im check on gate pin Q0906 i got value 1.8v. i pull out the mosfet and test its ok. and then i measured again pin pad no 4 and got value 9.67v. checked on component resistor R0930 also 9.67v C0926 one side 19v anotherside 9.67v

so what the next clue? please help me.

[sasser]

Re: compaq CQ43 cant on list volt measured

im got pin4 3.6v on mosfet Q0906

update info:

now im reflash bios and i see on PSU current ampere is 5.0A means short some where. mosfet at Q0906 very hot when touch with finger. im check on gate pin Q0906 i got value 1.8v. i pull out the mosfet and test its ok. and then i measured again pin pad no 4 and got value 9.67v. checked on component resistor R0930 also 9.67v C0926 one side 19v anotherside 9.67v

so what the next clue? please help me.

[whaldsz]

Re: compaq CQ43 cant on list volt measured

update info:

now im reflash bios and i see on PSU current ampere is 5.0A means short some where. mosfet at Q0906 very hot when touch with finger. im check on gate pin Q0906 i got value 1.8v. i pull out the mosfet and test its ok. and then i measured again pin pad no 4 and got value 9.67v. checked on component resistor R0930 also 9.67v C0926 one side 19v anotherside 9.67v

so what the next clue? please help me.

1. Resistance of R0906 with respect to ground?
1. pin4 of Q0906 is connected to R0930 but your measurement on pin 4 of Q0906 IS 1.8v and R0930 is measured as 9.67v? Please check this measurement again.

2. how about pin 1,3,6, 8, 13 of U1001, what are the voltage readings?
3. Resistance of L1001 and L1002 to ground?

[ktmmotocross]

Re: compaq CQ43 cant on list volt measured

thats some big difference between measures

what is voltages and resistance to ground on q0903?

[sasser]

Re: compaq CQ43 cant on list volt measured

1. Resistance of R0906 with respect to ground?
1. pin4 of Q0906 is connected to R0930 but your measurement on pin 4 of Q0906 IS 1.8v and R0930 is measured as 9.67v? Please check this measurement again.

2. how about pin 1,3,6, 8, 13 of U1001, what are the voltage readings?
3. Resistance of L1001 and L1002 to ground?

1. Resistance R0906 zero ohm both side
im measure again sorry for my mistake and i got same value at all line connected to Q0906 pin4. which means 2.7V on pin 4 ,2.7v on R0930 and 2.7v on pin no 3 U0902
2. now zero volt after short become. before this not hot component and u can see my port ealier.
3.L1001 & L1002 both side zero ohm

[sasser]

Re: compaq CQ43 cant on list volt measured

thats some big difference between measures

what is voltages and resistance to ground on q0903?

resistance to gound on Q0903 is zero ohm and no beeps from continuity selected
then the volt i got 2.7~2.8v

Thanks for help me

[sasser]

Re: compaq CQ43 cant on list volt measured

update:

sorry all my friend. i know why Q0906 was shorted. i check on detail i found Q1004 was wrong place. then i do correction with pull and place back

now no shorted and no hot area there. but still cant power on the laptop. i read my PSU measure 0.0250A more than normal
pin 1 0volt ,3 1.21v,6 0v, 8 0v, 13 3.47v of U1001

[ktmmotocross]

Re: compaq CQ43 cant on list volt measured

PIN 3 must be 2v, VIN?

[whaldsz]

Re: compaq CQ43 cant on list volt measured

Replace U1001. This chip is broken.

[sasser]

Re: compaq CQ43 cant on list volt measured

VIN at U1001 is 2.54v . i need to replce this ic fisrt ? then i noticed here