I have an E14 Gen 4 AMD that shows no signs of life.
When connected to the charger the board initially drew 30 mA at 10 V.
The thermocamera showed a hot spot at one edge of the PD controller. I therefore replaced the PD controller, after which the board drew 5 mA at 20 V.
Further investigation revealed that the power switch UT5 (NX20P5090UK) was not activated. The EN# signal is missing. This is supposed to be generated by the PD controller.
From then on I started using the battery instead of the charger.
With the battery the main power rail V9B+ is present (11.4 V) but all the other power rails are off.
I then looked at 3VALW and 5VALW. Both require the enable signal EC_USM which is supposed to be provided by the EC.
However, the EC is powered by 3,3 V but does not provide this signal.
Next I measured various resistances against GND:
PL4903 3VALW 400 Ohm
PL4904 5VALW 400 Ohm
LDO3 4 kOhm
LDO5 40 kOhm
These values are comparable to those of an E14 Gen 3 AMD mainboard which I am using as point of reference.
I then took the same measurements for all other power rails. I also opened various jumpers to rule out some defect behind the jumper.
All the measurements turned out to be reasonable.
What else could I do to trace down the fault?
schematics can be found here: https://www.badcaps.net/forum/troubl...e501-schematic
When connected to the charger the board initially drew 30 mA at 10 V.
The thermocamera showed a hot spot at one edge of the PD controller. I therefore replaced the PD controller, after which the board drew 5 mA at 20 V.
Further investigation revealed that the power switch UT5 (NX20P5090UK) was not activated. The EN# signal is missing. This is supposed to be generated by the PD controller.
From then on I started using the battery instead of the charger.
With the battery the main power rail V9B+ is present (11.4 V) but all the other power rails are off.
I then looked at 3VALW and 5VALW. Both require the enable signal EC_USM which is supposed to be provided by the EC.
However, the EC is powered by 3,3 V but does not provide this signal.
Next I measured various resistances against GND:
PL4903 3VALW 400 Ohm
PL4904 5VALW 400 Ohm
LDO3 4 kOhm
LDO5 40 kOhm
These values are comparable to those of an E14 Gen 3 AMD mainboard which I am using as point of reference.
I then took the same measurements for all other power rails. I also opened various jumpers to rule out some defect behind the jumper.
All the measurements turned out to be reasonable.
What else could I do to trace down the fault?
schematics can be found here: https://www.badcaps.net/forum/troubl...e501-schematic
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