Jetson NX power LED is always off!

I have a Jetson NX. when I connect the 19V power, the LED remains off. But other functions are OK.
I checked the 5V and 3.3V pins and they were OK. But I did not check other pins.
what is the problem?

Do you mean LED DS1 (you can find the P3509 schematic in DLC)? What’s the output level of pin 127, “PWR_LED_CTRL” (GPIO04)? It is the control pin of LED DS1. It should be high to enable DS1 when 5V is applied. Please check that on your board first.

with a multi-meter I checked the voltages:
pin04 was 5volts
pin03 was zero

What do you mean pin03/04? Have you check the P3509 schematic and PWR_LED_CTRL signal? Please confirm it is DS1 or not?

it is DS1.
you told that: “GPIO04 should be high to enable DS1 when 5V is applied”.
how should I check this?? and how should I put it in HIGH mode?

You can use multi-meter to measure the voltage of pin1 of Q1 (or any pin of R1). That’s to check if the PWR_LED_CTRL is correct during power on.

On the Jetson NX there are 40 GPIO pins [J12]. I checked the voltage of GPIO #4 pin. It was 5 volts during power on.
is that what you mean? if not, please send me the picture of what and where to check the voltage. thanks

Pin 4 of J12 is 5V supply not the control pin of DS1. Please measure the pin of R1 as you can see in the P3509 schematic as I pasted here.

Dear Sir,
As I asked before, please show me the R1in a real picture of the jetson board. I am not able to find it on the board. please show it on some images like these:

Dear sir,
Did you see my request?

you can get its location by searching R1 in P3509_A01_PCB_assembly_drawing.pdf in Jetson Xavier NX Developer Kit Carrier Board Design Package (P3509 A01). Next time, you can get any component location by this way.

Dear sir,
I detached the main part (GPU) from Carrier Board. Then I plugged the power. after that I checked the R1 voltage by multimeter.
The R1 voltage is Zero.
what should I do next.
what is the problem?

What do you mean “detached the main part (GPU) from Carrier Board”? Which component do you mean? The R1 voltage indicates the control signal to DS1, if it is low the LED won’t be ON.