I'm a little unclear of the history of your vehicle, and how you're connecting the radio with the headlights. If I understand correctly, interior lights and headlights are working ok, but the things operated by the ignition switch do not work every time.
It sounds like you have a bad ignition switch or connector. There are three or four separate switches built into the assembly. The one that turns on power to the radio, power windows, and dash often overheats and melts the plastic housing or the connector. If the connector melts far enough, it can affect the starter circuit too.
Similar problems can be caused by broken wires in the steering column if you move the tilt wheel often. Try changing the position of the steering wheel to see if it makes a difference. If it starts working, the wires need to be repaired.
Monday, March 23rd, 2009 AT 12:45 AM