I put my scanner on it and got P1111 and C1165

Also noticed the gas cap was loose and tightened it.

C1165 seems to be a rear ABS sensor so I'll check that.

I erased the P1111 and the CEL went off............for a while.

Now it's back on.

Do I need a special scanner to read the codes on a Jag?

 

Erasing P1111 rather suggests you didn't look it up (Search or get codes PDF or get JTIS - all are free here).

You don't need a special OBD tool for standard OBD stuff but there again not every tool is built properly. There's a detailed thread in General Tech of ones people have tried and reported about.

 

Well, now I have a P1000 code which I know means the diagnostic check is not complete. But, the CEL is on and there's no code for that.

 

CEL (properly, MIL) and no code. Don't think that even meets the law (*)! Something's very odd. Suspect your OBD tool.

(*) yours or mine

 

If you read a C1165 you've already got the special tool. If you haven't fixed that, I suspect that is what is illuminating your MiL

By "went off for a while" do you mean for about 100 yds of driving or until you hit 5 or 10 mph? I think the ABS system does a BIT check after every start-up and if a malfunction is present, you don't get an indication until you pass the neighbor's house two doors down (in my case, anyway, your mileage may vary)

 

During a 10 mile ride yesterday, the CEL and ABS Fault went off. Then I went over some railroad tracks and the ABS came back on.
After stopping for a while the CEL came back on when I restarted.

The car runs fine and the brakes feel fine.

 

Check the wiring on the wheel hub. I had to replace my front passenger hub and got a cheap one off ebay. About six months later the plastic cover that has the sensor just fell loose. I haven't changed it back out yet but have pressed it back in place. When it falls loose I get the ABS light and of course my Traction Control gets turned off.

This may be way off but you mentioned a code about the rear ABS sensor. Might help to look.