Yep, put some new batteries in and you should be fine. If it's like the P3D, it flickers as an indicator of low batteries. If that doesn't work, I don't know what the problem is.
You all are correct. Mine had flickered on high...indicating that they need replaced. So when I used it on low for awhile, it eventually got dim and even flickered on low. It did this on my Tenergy rechargeable's.