Possibly a neutral lockout switch, possibly a bad connection, possibly an ignition switch.
I'll include a link to a video below that will show you how to repair the ignition coil in your Ford F250 or F350. hope this helps.
remove column dust covers, along with ignition switch. then remove retaining
Remove upper and lower shroud (3Screws). With key in ignition and in the on position look for a ball detent and press it in with a small Philips head screw driver while pulling on the key. The entire cylinder lock will then come out.
i have a f350 7.3 an my low range is flashing on what does that mean
if it is 92-97 remove steering column covers then using a small drill locate small hole on the underside of column under the ignition switch drill out pin inside and slide switch out then spend about 13 dollars on new switch slide new one back in put covers back on column
Check the fuse, bulbs or there is a push button switch above the brake pedal that may need align or replace
7.5L?
yes
what engine size do you have ?
A good oiling of the door latching device with a thin oil works in most cases. Replace the door ajar switch that plugs into the door latch from inside the door. These switches are notorious for going bad...causing the dome lights to come on randomly, even when parked with key out of ignition, causing dead batteries, etc. Moderate difficulty to change switch. Part costs about $20. Not a job for rookies.
on the side of the dash