The ignition on a 1990 Ford F-150 is common to other Ford trucks and vans produced in the late 1980s and early 1990s. It's a common locking ignition--that is, it requires the ignition key to turn the switch and start the F-150. When the switch is turned, it sends a signal to a solenoid that closes the circuit to the F-150's starter and starts the engine. As your F-150 ages, the ignition switch can fail due to repeated use, requiring you to remove it from the truck for replacement.
Put the key for the F-150 into the ignition switch and turn to the "On" position. This is required to unlock the ignition before removal.
Locate the access hole for the ignition release pin that is located beneath the ignition switch.
Insert a 1/8-inch or smaller drill bit into the access hole and depress approximately 1/8 inch to activate the release pin holding the F-150 ignition in place.
Pull the ignition lock cylinder assembly and remove it from the steering column.
