On an '08 E-450 stripped chassis(not an truck, i know) with gas engine.
The "security" light(car with lock icon) flashes rapidly when the ignition is turned on and the digital odometer goes to flatline. After one minute the icon gives a flash code(?) of 1 - 6.
This vehicle is not PATS equipped.
Vehicle will not start or even crank. Batteries are up, starter will turn engine over when operated with remote push button starter.
Try resetting the KAM by removing the battery ground cable for 5 minutes. Maybe check fuses 14 and 15 in central junction box. Thats all I can think of without a scanner. I cannot find a flash code chart for the PATs system
In the hope of maybe helping someone else out there.
In addition to above symptoms, found fuse #23(PCM and other) in underhood fusebox blown, also Rotunda scanner would not connect to PCM but would connect to Instrument Cluster module.
Replaced fuse and immediately blew on "ignition-on".
Found, drivers side Heated Oxygen Sensor connector power wire had rubbed through shorting directly to ground at rear of LH cylinder head.
To test, I removed fuse #23 and vehicle exhibits exact symptoms, replace and all is normal.
Hope this info may help someone.