[strictlypersonl]

The ignition switch circuit does not include the lights, so if the head and parking lights are effected, the problem is elsewhere.

If you have a circuit breaker mounted next to the starter solenoid, bypass it temporarily (put both its wires on the same terminal) and see whether that fixes the problem.

If there's no circuit breaker or the problem persists, trace the power from the battery to the ammeter and back to the fuse box.