I replaced the battery and still having same problem

Here is an example of DELL diagnostic lights

DELL System Diagnostic Lights

The power-status light indicates the power status of the computer.

These are the power states:

Solid white                         Computer is in S0 state. This is the normal power state of the computer.

Blinking white                  Computer is in a low-power state, S3. This does not indicate a fault.

Solid amber                       Computer is experiencing a boot failure, including the power-supply unit.

Blinking amber Computer is experiencing a boot failure but the power-supply unit is functioning correctly.

Off                                         Computer is in sleep state, hibernation mode, or turned off.

•  The power-status light may also blink amber or white according to predefined "beep codes" indicating various failures.
• For example, the power and battery-status light blinks amber two times followed by a pause, and then blinks white three times followed by a pause.
• This 2,3 pattern continues until the computer is turned off, indicating no memory or RAM is detected.

The following table shows different power and battery-status light patterns and associated problems

 Diagnostic light codes

Amber, White             Problem description

1, 2                         Unrecoverable SPI Flash Failure
2, 1                         CPU configuration or CPU failure
2, 2                         System board: BIOS or Read-Only Memory (ROM) failure
2, 3                         No memory or Random-Access Memory (RAM) detected
2, 4                         Memory or Random-Access Memory (RAM) failure
2, 5                         Invalid memory installed
2, 6                         System board; Chipset Error; Failure of Clock, Gate A20, Super I/O or Keyboard controller
3, 1                         CMOS battery failure
3, 2                         PCI of Video card/chip failure
3, 3                         BIOS Recovery 1: BIOS recovery image not found
3, 4                         BIOS Recovery 2: Recovery image found but invalid
3, 5                         Power Rail Failure: EC ran into power sequencing failure
3, 6                         Paid SPI Volume Error
3, 7                         Management Engine (ME) error. Timeout waiting on ME to reply to HECI message.
4, 2                         CPU Power cable connection isssue.

Amber blinking? That means the power supply is good, according to DELL.

Dell XPS 18 Battery Replacement

Unplug power supply/charger. Take out the battery and and press the power button to dischage any power. After that is done, with the battery uninstalled, plug in the charger. Press power button. Does anything happen? Any flicker on the screen, beeps or lights. Describe.