I have a 2006 XL7 with 19000 miles on it. I've had absolutely no problems with it except recently the keyless entry system has started acting up. I've searched the forums and found alot on reprogramming the keyless remote. My problem is that after I reprogram it only works for about a day and then stops. I've tried replacing the batteries. I'm trying to see if its just something simple before I take it to the dealer. Any suggestions?

If reprogramming it fixes it for a little while, it sounds like your keyless box in the car has gone bad and keeps resetting itself.

Does it stop working every day at a specific time, or only if you leave your car off for a period of at least X hours?

Do you have the same problem with both remotes?

The problem is with both remotes. There isn't a real pattern to the problem - it intermittenly works and then doesn't work. I kind of thought it was the box but I thought I'd see if anyone else has had a similar problem.

If the problem is with both remotes, then yea it probably is the box.  Might be a short somewhere, or just the box going bad.  You could probably put an aftermarket box in.