Dell Precision 7710 - it can not be turn on and off with the switch

[ajc333]

Hello.
Markings on the board AAPB0 LA-C551P REV:4.0 (A03). The laptop came to the service with the fault of shutting down after a few minutes of load such as a game. It turned out that the smaller fan was damaged, a complete original cooling system from dell was ordered and from this time everything is back to normal. The problem, however, is the inability to turn on and off the laptop with the switch. On the switch board, the voltage drops from 3V to 0V when the switch is pressed.
On the connector on the board (from the right side) I have the following voltages:
n1. - 3V after pressing the switch drops to 0V
n.2 - 5,1V
n.3 - 0V
n.4 - 2,35V
n.5 - 0V
n.6 - 0V.
After applying voltage from the power supply the laptop turns on by itself, closing the system the laptop turned off, but after about 10 seconds it would wake up again. I updated the bios to the latest one and now after applying voltage from the power supply the laptop turns on by itself, closing the system it does not wake up anymore. However, on the battery itself it cannot be turned on from the button. The battery charges correctly.
Please give me further advice.

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[mon2]

Re: Dell Precision 7710 - it can not be turn on and off with the switch

Do you have a WLAN card installed? Remove it and test again.

The WAKE# signals should be reviewed if the logic board does not wake up.

Be sure that you are using the proper Dell power adapter for this unit.

Does the BIOS show the correct power adapter is being detected?

Check the voltage to ground of the PS_ID circuit. Post the measurements.

The power adapter must be detected properly for the logic board to function.