I have an 04 FX4. Having starting problems after reaching operating temp. It has never failed to start when cold. When I turn the key, the indicator lights activate, the solenoid relay clicks, but no crank. After holding the key on "start' for a few secs, the LED starts to flash rapidly. I changed the starter (that was fun.... hoping it was the solenoid). I took it to a key shop..... they scanned it and said it indicated a problem in the transponder receiver antenna, or the module. Is the antenna replaceable? Do the keys have a power source that depletes over time? Should I just run a wire to the solenoid terminal and run it through a dash switch? (takes ya back, huh?) Thanks, I'm a newbie, but you probably knew that.

 

Answering my own question...... turned out to be pinched wires in the steering column.