Not powering on starts led blinks 4 times then off

[Stevie2001]

Acer DAOZK6MB6D0
REV: D

It had a blown diode replaced it then it had few other resistors blown next to ic isl6251 replaced them and now on dc power supply 19v stable but drawing 1amp thats it not drawing any when i presspower light blinks 4 times

The resistors was showing hot so this is why i replaced them with the similar ones.

Using thermal camera i can se the isl6251 ic getting heated up look at the image.




Please tell me what to do.

[budm]

Re: Not powering on starts led blinks 4 times then off

What are the values of the blown resistors?
What pin of the IC those blown resistors connected to?
What resistance do you get on the VCC pins of the IC with ref. to GND?
What resistance with ref to GND do you get on the output end of those blown resistors?
Resistor get hot if the load side is shorted or has very low resistance so more current will flow and causes it to heat up beyond its rating.

[Stevie2001]

Re: Not powering on starts led blinks 4 times then off

What are the values of the blown resistors?
What pin of the IC those blown resistors connected to?
What resistance do you get on the VCC pins of the IC with ref. to GND?
What resistance with ref to GND do you get on the output end of those blown resistors?
Resistor get hot if the load side is shorted or has very low resistance so more current will flow and causes it to heat up beyond its rating.

I will get back to you with more info values.
Voltages of pins and resistor and where the resistor belong to.

Do you think changing the ic might fix this.
The value on blown resistor is
01x
89c
Caps x1 10ohm i think
2r2 replaced with biger 2r2 sinc i salvaged that
30x replaced with 20 ohm

1 dioid near ac jack blown value pj9n6 replaced with same size of diode not value still power is flowing so am assuming its ok.

If you check shematic maybe you will se what it connects to.

[SMDFlea]

Re: Not powering on starts led blinks 4 times then off

If you have the schematic upload it.

[Stevie2001]

Re: Not powering on starts led blinks 4 times then off

When i press power orange light blinks 4 times nothing else happens.

Acer 5739

[budm]

Re: Not powering on starts led blinks 4 times then off

Where is the schematic?
BTW, you need to provide the damaged parts designators (I.E. R123, C123, D123, L123, etc.), without it you cannot tell which part is which.

[Stevie2001]

Re: Not powering on starts led blinks 4 times then off



Pd10
Pr22
Pr26
Pr21
Pc24
Pr24 use to get heated along side pu3 now replaced these they ok not heating only pu3 heating up with thermal and with finger cant feel it

[SMDFlea]

Re: Not powering on starts led blinks 4 times then off

The cap at PC24 wants replacing.

Quanta ZK6 , page 31 .

[Stevie2001]

Re: Not powering on starts led blinks 4 times then off

Can i ask is this why when i press power the orange light blinks 4 times nothing happens after that is that the part causing it

Pc24 shows in shematics 01uf 50v

[SMDFlea]

Re: Not powering on starts led blinks 4 times then off

I'm looking at your picture, it looks like the pad is damaged under pin 1 of pc24 and pin 2 isn't soldered down ? .

[Stevie2001]

Re: Not powering on starts led blinks 4 times then off

I'm looking at your picture, it looks like the pad is damaged under pin 1 of pc24 and pin 2 isn't soldered down ? .

I fixed that up.
After doing all caps resistors when i connect dc power supply 19v ok with 2amps without battery now when i press power button the orange light blinks 4 times then off.

Nothing else turns on no fan nothing i should be expecting blue light.

When also when i click power button the amp remains at 2 on dc power supply its not drawing any amps when i click power.

Can that ic be the main problem to all this

[SMDFlea]

Re: Not powering on starts led blinks 4 times then off

"30x replaced with 20 ohm"
"1 dioid near ac jack blown value pj9n6 replaced with same size of diode not value"

You should replace parts with the same value`s. Heres the datasheet for the ISL6251 , look at page 2 and page 8

[Stevie2001]

Re: Not powering on starts led blinks 4 times then off

"30x replaced with 20 ohm"
"1 dioid near ac jack blown value pj9n6 replaced with same size of diode not value"

You should replace parts with the same value`s. Heres the datasheet for the ISL6251 , look at page 2 and page 8

Yeh thanks was usfull
I will get the original parts ordered.

For example if a resistor marking is 30x does that mean i only have to get that? In datasheet it shows the ohms and i thought as long its same part and ohm it should work?.

How sill i test isl6251 if its bad or good even thermal showing heat.

[SMDFlea]

Re: Not powering on starts led blinks 4 times then off

"For example if a resistor marking is 30x does that mean i only have to get that? In datasheet it shows the ohms and i thought as long its same part and ohm it should work?."

The resistor marked 30X has a 1% tolerance .

http://www.marsport.org.uk/smd/res.htm

I`d replace the isl chip,diode and resistors.

[Stevie2001]

Re: Not powering on starts led blinks 4 times then off

"For example if a resistor marking is 30x does that mean i only have to get that? In datasheet it shows the ohms and i thought as long its same part and ohm it should work?."

The resistor marked 30X has a 1% tolerance .

http://www.marsport.org.uk/smd/res.htm

I`d replace the isl chip,diode and resistors.

Sir i will but i wanted to say since i havnt got new ic yet what if i take that ic out will it power on?

Video
http://sendvid.com/s5hpysqf

[Stevie2001]

Re: Not powering on starts led blinks 4 times then off

I was thinking about maybe other component maybe heating the ic so what are the main voltages am looking for
19v 3.3v 5v

[Stevie2001]

Re: Not powering on starts led blinks 4 times then off

Pq29 pq28 pr135 phase 1.05v missing.

Guys if you can check am having suspicion on part pu7
As it is near the power jack and giving voltages read below.

Pin1 00.0v should be +1.05v shown on boardview
Pin3 03.6v should be 1.05v_FB
Pin4 1.94v Boardview shows HWPG_1.05v
Pin8 00.0v should be LGATE-1.05V
Pin11 02.0v should be PHASE-1.05V
PIN12 02.1V should be UGATE-1.05V

[SMDFlea]

Re: Not powering on starts led blinks 4 times then off

Does the battery charge light come on if you put the battery in . If the battery charges up ,try turning on with just the battery .

[Stevie2001]

Re: Not powering on starts led blinks 4 times then off

Does the battery charge light come on if you put the battery in .

It blinks once then no more and using thermal i can se the left side of battery heats up.

By the way the reading values on pu7 does it seem ok or not sir.

[SMDFlea]

Re: Not powering on starts led blinks 4 times then off

just replace the isl and other parts, take it from there .