All of a sudden my 78 truck will not start. When you turn the key nothing, no clicks etc. It will turn over when you bridge the wire on the relay. I also replaced that relay. Anything else to check thats easy to access? I have a power probe, can I apply 12v to the orange wire coming down from the key/steering wheel harness to test the system and rule out the ignition switch?

hi
nutral safty switch or more likly wiring to it ?

or nss wiring to relay swith ?

The ignition switch has a master plug that joins the under dash harness about a foor from the base of the steering column. It is possible to kick it with your foot and dislodge the connection if it is old and brittle. If the connection is loose or the switch itself is faulty, the key will get you nowhere.

Thanks, traced wire to under the truck and found 3 wires pulled loose from the trans. Starts fine now.