My Dell Latitude E6540 refused to power on via AC adaptor or charge the battery. It can power on from battery thought.

Replaced with a new AC adaptor but in the end, it is the 3 MOSFETs on the motherboard kaput. Replacement took about a week and cost about 300 bucks.

IMO, it is quite expensive to repair locally as u can buy a refurbished motherboard from AliExpress for the same price and wait about 2 months.