Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

[fuxxy]

Just picked this up from the trash @ work.

Dell Latitude E6320. Unsure of battery charge level. I *DO* have the docking station.

When plugged into power adapter (even my wife's - known good), I get no lights from the laptop. Removed battery, press power button - still nothing.

Tried the same procedure using the docking station to eliminate DC Jack wire/solder issue, same exact results.

I've removed the mainboard from the laptop and see nothing out of the ordinary. What are some ideas I can try next?

[fuxxy]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

Battery voltage is 11.92V
Label on battery says 11.1V, 65Wh

[diif]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

Here's the schematic.

[fuxxy]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

DEAR LORD thanks so much for the schematic!

Current path:
1) Battery and AC adapter supply +PWR_SRC
RESULTS: GOOD
PJP44 (+PWR_SRC) - 11.1V with only battery, 19.6V with AC adapter plugged in

2) IC "PU2" takes +PWR_SRC and turns it into +5V_ALW, +15V_ALW, and +3.3V_ALW
RESULTS:BAD
PJP49 (+15V_ALW) - 0.0V
PJP45 (+5V_ALW2) - 1.5mV(essentially zero)
PJP63 (+3.3_ALW) - 0.0V

Closeup of PU2 attached.

[fuxxy]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

Can someone offer me some guidance on how PU2 works and how to test for proper operation?

The chip is a SN0608098.

[fuxxy]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

Namely, does it require gate voltage to "turn on"?
Or is it simply apply +PWR_SRC and ground, and it automatically output +15V_ALW, +5V_ALW, and +3.3V_ALW ?

I've searched everywhere I know of, and can't find a datasheet. It's manufactured by Texas Instruments, but it doesn't come up in a search on TI's website.

[fuxxy]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

+15V_ALW Test points are PJP49
+5V_ALW Test points are PJP47, PJP48
+3.3V_ALW Test Points are PJP9, PJP50

[trebo]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

The chip is a SN0608098.

are you sure that's right, or is it SN608098

[fuxxy]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

The schematic says SN0608098
The chip says
SN
608098

Thanks for the heads up, I didn't think I needed to be that precise

[trebo]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

Pm6686 = isl6236 = sn608098.

[khaahk]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

Seems like a spill victim from 1st closeup of PU2.
PU2 should output voltage if enable signals are present and VIN is present.

[fuxxy]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

Seems like a spill victim from 1st closeup of PU2.
PU2 should output voltage if enable signals are present and VIN is present.

Quite possible, I picked up this laptop from work and have no idea of it's history. It was placed in the bin, in a covered area, but still outside in the texas humidity.

from the MAX17101 datasheet, it has a separate 3.3V "RTC" pin, I do get 3.3V from that.

I'll doublecheck at the actual pin to eliminate trace damage.

Which is "Enable"? Pin 4?

Pin 4 - ONLDO - Enable Input for LDO. Drive ONLDO high to enable the linear regulator (LDO) output. Drive ONLDO low to
shut down the linear regulator output.

If it is, in fact, pin 4 - and it is driven high - what sort of voltage should I see? Around 5V?

EDIT:
It looks like pin 14 and 27 are also Enable pins.
4 is to turn on LDO regulator - Measured 0.263V
14 is to turn on "Output 1" - Measured 0.263V
27 is to turn on "Output 2" - Measured 0.263V

Still curious about "good" voltage. Trying to determine if the problem is with the chip itself, or the supply circuit.

[khaahk]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

4-5V should be "good", datasheet states that it should VCC voltage.
What is VIN voltage on PIN6?

[fuxxy]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

Pin 6 VIN is 20.0 volts with adapter plugged in. Roughly 12 volts with only battery.

[khaahk]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

Does the chip get hot?
PIN 7 output should be 5V.

[fuxxy]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

Chip does not get hot - Roughly 105mV on pin 7

[fuxxy]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

I'm concerned that some sort of logic on the board is shutting the regulator down. Would it be logical to remove the regulator and check pins 4, 14, and 27 for +5V?

[khaahk]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

The PIN4 - ENLDO should get its high state from divider PR42-PR44 using signal ALWON which is coming from MEC5055 microcontroller. I think that MEC5055 is powered from PU14 3.3V_ALW signal. The PU14 seems like some kind of power/charging selector controller. Check PU14
pin 18 - output 3.3V ?
pin 9 - input 3.3V ?
pin 1 - DCIN adapter voltage?

[fuxxy]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

PU14
Pin 1 - 19.8V
Pin 9 - 3.28V
Pin 18 - 0.1mV

[khaahk]

Re: Dell Latitude E6320 - Completely dead, no {lights,fans,CPU heat}

Seems like PU14 is not outputting 3.3V to MEC5055. Why - good question, some missing control signal maybe, maybe its not working as it should.
Does PU14 get hot? Resistance from pin18 to gnd?
If not then can you insert 3.3V manually to PIN18 and see what happens.