Do you have a multimeter and know how to use it?

 

The basic functions ohms, AC/DC stuff like that.

 

With the engine off and the key to the run position and the transmission in reverse should the reverse lights come one? Or does the engine need to be running? Think i answered my own question.

 

Whether the engine is running or not is irrelevant as long as the ignition switch is in the RUN position.

 

Which fuse did you check, #5?
If the fuse is indeed good then check for power going in on pin 9 and out of pin 11 on the DTR sensor. See the PDFs for the diagram and connector pinout.

 

Alloro is spot on as per the norm. The other item that can throw a monkey wrench in the works is the Ground connection to the frame/body. If either side of the circuit is not in proper shape (corroded/broken wiring/terminals, etc), the circuit won't work as intended.

Test it as Alloro said first to ensure you are receiving 12v at the lights first. Once that is known, then check the ground. IIRC, they are grounded on the driver's side frame rail close to the rear tire.

 

STOP!

Original poster: Explicitly identify that you are working on a 99 F250 Super Duty. If you're working on one of those bazterdized [sic, swear filter ]F150s with F250 badges, it's a completely different critter. ALWAYS explicitly identify what you're working on. I, for one, don't bother wasting time poking around to try and find out stuff that you should have identified up front.

alloro: I get "drawing errors" in Adobe Reader when I try and open the two files you attached, it appears they may corrupted as seen on my end or my install of Reader is wacked. In any event, I suspect they're the drawings for the light duty F150/250 instead of the F250 Super Duty as F5 supplies that circuit on the light duty version. The Super Duty electrical layout is completely different and its schematic is attached.

 

Your drawing shows the same thing mine did, in on pin 9 of the DTR and out on pin 11 and off to the reverse lamps.

 

Yes, the DTR is the same, but your schematic was of the half ton's circuit which has a completely different power supply than the SD.

 

One is fed from fuse 28 and the other from fuse 5, other than that they're identical wiring.

 

Similar (as expected), absolutely not identical. Different fuse boxes, connectors, etc.