I need an outside power source for running board lights

It sounds like your solonoid is gone.

does sound like a circuit board problem , only way to tell is get the circuit boards checked out for loose/cracked connection's faulty parts etc , check for continuity along the circuit to the brake light connector , this site might help you get started as i don't know your level of this type of work,
How to Find Fault in Circuit Board Techwalla com

are you sure that you put the right bulb in? Some of these bulbs look very similar, (like a 3057 and 3157 or 3156) but they are different. A customer came in with this problem and the problem was that they put a bulb with a single filament in when it was supposed to have a dual filament. the bulbs looked the same and they just grabbed them off the shelf instead of asking the parts guy what their vehicle called for.

Check the fuses. Under the steering wheel. If the fuse for the dash lights is blown, replace it. If it blows again, replace it again and look into what could cause the short.

The lights may also need to be changed in the dash.

The switch to turn on dash lights might be bad. If this is so, outside running lights won't work either.

IN the dash board on the drivers side under a little door the opens to put change in just to the left of the drivers steering collum this door can be removed and the fuse names are on the bnack of this little door. If the dash lights aren;t working your tail fuse might be blown as the rear running lights and the dash lights share the same circuit on purpose. If your tailights are'nt working your dash does light up to let you know.

there is a known problem with the circuit board the bulbs sit in ..most parts stores sell them in the "help" section or "dorman products" section if you want to check it properly you will need a test light and a friend...first thing you must attach the test light end to a good ground source put the other end in to the electricle connector one wire at a time of the brake switch push the pedal if it illuminates on a wire only when the pedal is pushed it is getting powered up and functioning next go to the back of the truck and do the same with the tail light ..use your friend to push the pedal and test for power present in a wire only when the pedal is pushed if that is there then the power is getting to the tailight next you must check for ground so put the test light end on power you might need a piece of wire to extend to the back ..be carefull probe the plug if the test light illuminates there is a good ground there and you need to change the board

Hello! Either the fuel pump relay isn't pulling or the inertia switch needs to be reset...The relay is is under the shield at the air cleaner support bracket...Yellow wire is power feed from fuse link "W"...+12 volts must be present on the Brown wire that exits the relay...From there the Brown wire goes to one side of the Inertia switch and exits the switch on a Red/Yellow wire...With the key on +12 volts must be on that Red/Yellow wire...Inertia switch is located on the drivers side floor board, to the left and above where the steering column passes through the floor board...

Guru....Saailer

I’m happy to help further over the phone at https://www.6ya.com/expert/david_6df67de3b14de867

go to the fuse panel find the fuse that is powered by the ingtion source take a test light turn key on to see which one has power then use that fuse slot the make fuses with a wire connceter on it ofr your power source

If you have a information menu in the dash, besides all of the gas mileage and trip functions- there is another menu.
On this menu you are able to set the horn to chirp when setting the alarm, park assist for the mirrors and so forth. One of the functions should be the on/off for the running boards. We had a Lincoln Aviator without running boards, but I believe I read about it in the owners manual. The setting was probably lost when you changed the battery.

replace relays and fuses for the power seat and windows.change dash light bulbs.if bulbs are good you got wiring problem check ground wires.