There is likely a fault with at least one of three items: It's a process of elimination to figure out where the problem lies, or at least where it doesn't lie. For example, if your AC adapter is recognized and works on another Dell laptop, then the problem is likely your charging jack or charging circuit. Check if the light is lit at the plug end of the AC adapter or on the adapter block. And see if that light remains lit when you plug it into the laptop's jack. Check the centre pin inside the AC adapter's barrel plug. That pin is required for identification of the adapter as a Dell adapter. If it's bent, you could try to gently straighten it. Use 99% isopropyl alcohol and a swab to clean the inside of the charging jack and the barrel plug. If you do succeed in booting the laptop, hold F2 while booting, to enter BIOS. See if the AC adaptor is recognized. Try another genuine Dell AC adapter of at least the same wattage/amperage. If that second Dell AC adapter works, then the fault is likely with your AC adapter. If it doesn't work, then the fault is likely with the jack or the circuit. The jack is a relatively inexpensive item that is not difficult to replace for someone experienced in working on laptops. If a good AC adapter and a new jack won't work, then the fault is likely with the charging circuit on the motherboard, which would normally require replacement of the motherboard. Also, it's worth trying a reset: If the laptop will boot with battery disconnected but not when connected, then at least part of the problem is with the battery. But, with what you describe, it's likely a fault with AC adapter, charging jack, or motherboard.
My computer won't turn on and the charger turns off when I plug it in, what can I do?
Dead Laptop Dell Inspiron 15 7000 No Power Charger light goes OFF