Dell precision 5530 won't turn on

My Dell Precision 5530 will not power on and displays a continuous 1-blink on the keyboard light when i try to switch it on and the keyboard light blinks continuously when i plug the power adaptor in. I’ve already tried the following troubleshooting steps:

1. Checked the power adapter (confirmed working).

2. Performed a hard reset by holding the power button for 30 seconds.

3. Opened the back panel and inspected for a CMOS battery but couldn’t locate one.

4. Disconnected the internal battery, drained residual power, and reconnected it.

5. Attempted the Ctrl + Esc BIOS recovery process, but no recovery screen appears.

I suspect a BIOS corruption or hardware issue with the motherboard or power circuit. Please advise on further steps or repair options.