If anyone can track down what DTC 900 means that would be fantastic.
So far, it has not disabled anything, or affected performance, and has triggered no warning lamps. I would not have known about it unless I was specifically looking with a scan tool.

I could not find it in my Service Manual that has an extensive list of DTC
( diagnostic trouble codes ). Most codes are 4 digits. Ones that are not are preceded by zeros in the Manual. Such as 0073. So seeing just 3 digits was very weird by itself.

It could be just a erroneous packet of data, or perhaps something like anti-theft not working, which was not installed in the 2005's. I just don't know. So thanks. -John

 

This is probably not much help, but...

I thought Generic OBD II codes in the 900s were transmission-related. P0900 is "Clutch Actuator Circuit/Open"

HOWEVER... Many more recent resources indicate that the 900s are reserved for OBD 3. To make matters worse, newer Ford-specific stuff seems to skips them or is blank from 900-999. Wierd.

 

All codes will have the basic system identifier letter before the 4 alpha/numeric code. P is for power-train, B for body, U for can system and C is for chassis. Most likely a false code or incomplete code. The can bus on these FEH's are quite fast much faster than all other Fords. The scan tool manufactures are having trouble getting their scanners to reliably communicate.