Acer Travelmate P215-52 doesn't turn on

[diamon]

I have this laptop (Acer Travelmate P215-52 model N19Q8 ) here, and the owner explained to me story.
Somebody walked by at the table and tripped the power cable, the laptop did not fall down the floor (it was pickup before the landing on the floor).
The power connector on the charger does have damage.
.

The laptop did still work on the battery, the owner did try to attach a other original Acer charger (has more of these model Acer laptops) but the laptop did not work with this charger (did not charge the battery).
Now the battery is empty, and the laptop doesn't work anymore.

I have removed the board and placed a lab power supply to the VCC and GND (did removed the power connector from the board (in case of internal damage)), the laptop doesn't (no battery connected) want to power up.

I have done some measurements, I only have 19V on the 3 first (most right) bottom mosfets, the most left mosfet of those 4 there is no 19V in pressent. The mosfet (under the red line > AONR21357) has no 19V on the draine, only on the Source and no power on the Gate


Since a few days, I have a thermal camera and I have noticed that the 5 legs GAF chip is generating heat when I connect the power supply.
I have marked this part, it's the part under the red line.
.

I did not find a schematic for this board and can therefor not find out what this GAF part does.

Any ideas how to proceed...

[mcplslg123]

Re: Acer Travelmate P215-52 doesn't turn on

That 5 Leg IC is for usb power. You can safely de-solder it from mb. Check resistance on 5V coil before and after removing this IC and post it here. It seems you have +5V line shorted and there may be damage on other parts. The mb can be safely powered without this IC.

[diamon]

Re: Acer Travelmate P215-52 doesn't turn on

Thanks for your answer.
I wanted to make some voltage measurements , and I made a short between the VIN en GND pin
According to Google search, GAF could be a voltage regulator.
After removal of the IC, the voltages are still not there on VIN. Yesterday I did measure voltages there.

I did not find any schematics and perhaps boardview files, so no idea what could be damaged with this short I created.

[mcplslg123]

Re: Acer Travelmate P215-52 doesn't turn on

I wont suggest this approach. What is the resistance on 3V/5V coil?? Start with basics and dont jump to solution. Schematics does help but basic problems can be solved without schematic. Most of the newer mb schematic are either not avlbl or are there only on paid sites.

[diamon]

Re: Acer Travelmate P215-52 doesn't turn on

On the board there are 9 coils, how to determine which of those 9 coils is the 3V and the 5V.

[mcplslg123]

Re: Acer Travelmate P215-52 doesn't turn on

Look for pwm controllers and serach them on google and you will know there function. Once the pwm responsible for 3v/5V is identified, coil will be located nearby to that pwm.

[diamon]

Re: Acer Travelmate P215-52 doesn't turn on

I have searched all the IC with Google and did not find any PWM controllers where the schematics mentioned something that the chip is responsible for the 3v and / or 5v.
I did not find any information regarding "LJ=6M 3D9" and "L8=6L 56J" chips, any idea how I can find the reference / schematic for this chip?





Also the list with the other IC's I did find with Google:


51486 TI 991 AEKP DDR Memory Power Solutions Multi-Channel Converter DDR4 Memory https://cdn.badcaps-static.com/pdfs/...0f60c37124.pdf

e6936 AOE6936 30V Dual Asymmetric N-Channel MOSFET

5335 G5335 High Efficiency 10A Synchronous Buck Converter

bq24780s Hybrid Power Boost Mode Battery Charge Controller https://www.ti.com/lit/gpn/bq24780s

rt3602aj Triple Channel PWM Controller for IMVP8 Mobile CPU Core Power Supply https://cdn.badcaps-static.com/pdfs/...58750469f1.pdf

CYPD4126-40LQXI USB Controllers https://cdn.badcaps-static.com/pdfs/...0ab4fca35d.pdf

ALC255 Realtek

DPS1113 USB Power Delivery and other hot-swap applications

2898 Dual Ultra-Low On-Resistance Load Switch with Controlled Turn-On https://cdn.badcaps-static.com/pdfs/...818973bb1c.pdf

g781 Remote and Local Temperature Sensor

LVC601 Two-Channel 6-Gbps SATA Redriver https://www.ti.com/lit/gpn/sn75lvcp601

NPCT750A Trusted Platform Module (TPM)

PS8743B USB-C® Host Switch

5544V USB Charging Port Power Switch and Controller https://cdn.badcaps-static.com/pdfs/...b42ff38c38.pdf

PS8339B The PS8339 is a 1:2 demultiplexer IC that is connected to the output of a Dual-mode DisplayPort Source device. It outputs either a repeated Dual-mode DisplayPort signal from its DisplayPort output, or an HDMI or DVI signal from it's TMDS output. https://www.paradetech.com/products/ps8339/

[mon2]

Re: Acer Travelmate P215-52 doesn't turn on

See attached.

Anytime you find an '=' symbol, this is RICHTEK. The characters AFTER the '=' are datecodes.

So search for 'LJ=' and results in RT6258CGQUF.

'L8=' is RT6256BGQUF (Richtek.

Datasheets are attached. Aliexpress should have these. Just be sure to source the part with the same markings (except for datecode).

PS: Learned from School of @SMDFlea.

[diamon]

Re: Acer Travelmate P215-52 doesn't turn on

Look for pwm controllers and serach them on google and you will know there function. Once the pwm responsible for 3v/5V is identified, coil will be located nearby to that pwm.

3.3V (RT6256B): gnd > coil: 9.4K (with my second multimeter I got 24.1K)
5V (RT6256C): gnd > coil: 2.98k (with my second multimeter I got 45.5K)

See attached.

Anytime you find an '=' symbol, this is RICHTEK. The characters AFTER the '=' are datecodes.

So search for 'LJ=' and results in RT6258CGQUF.

'L8=' is RT6256BGQUF (Richtek.

Datasheets are attached. Aliexpress should have these. Just be sure to source the part with the same markings (except for datecode).

PS: Learned from School of @SMDFlea.

Thanks, I would never have found this myself

[mcplslg123]

Re: Acer Travelmate P215-52 doesn't turn on

Readings between 2 multimeter should'nt vary like this. Which readings to beleive?? Readings by 1st meter,if true, is problematic. however, if the 2nd meter readings are true, then the readings are fine.

[diamon]

Re: Acer Travelmate P215-52 doesn't turn on

I have done a measurement of a 47K resistor (not in circuit) with both meters.
The results are, that my measurements of 3.3V (RT6256B): gnd > coil: 24.1K and 5V (RT6256C): gnd > coil: 45.5K are correct.

[nickojean22]

Re: Acer Travelmate P215-52 doesn't turn on

did u solve the prob?