Toughbook FZ-55 will not power on at all

Are you getting any lights anywhere, or indications of power?

nothing, plug in the power adapter, no lights show up anywhere and hitting the power button no lights either

@neverside I know you said that the A/C adapter is brand new, but I prefer to check those things anyway. so try the basics first. First you want to check your power supply. Make sure it has the proper voltages. Check to make sure connectors are not bend etc. After that, check the charging port. Clean it of any debris etc, use a few puffs of air to clean it out. Check the DC-in jack of your laptop. Make sure there is no corrosion, debris etc. that prevents it from working.If none of this works, get a ammeter and see if your laptop draws any amperage from the charger. After that, you need to check and see if your motherboard even gets power. For that of course, you need to open it up. You also want to check if everything is properly connected on your "new" laptop since you really do not know the history. Check for hidden damage, like water damage, dislodged cables etc.

@oldturkey03

thanks for all that, so starting to open it up looks like it might have been part of a liquid spill. there's tiny traces of sticky residue alongside the fittings of taking off covers and modules....shame :(

@neverside that is the bad part about auctioned stuff. Never know what you are going to get. it is not the end yet, Take it apart and clean everything. Use something like this guide Riparazione danno da liquidi iPhone to clean the contaminated parts. check for missing or burned (damaged) components. You can always post some pictures of any area you may need help with, with your question. That way we can see what you see.