I dont see how it could, but the first time I used it I left it plugged in and the next time I went to start my car the battery was completely dead, not even jumpable. Its probably a coincidence, but could leaving it plugged to the ALDL port drain your battery?

 

Seems odd. Doesn't it automatically shut off after a while?

 

The manual for mine says it should power off automatically if you don't hit any buttons for 30 minutes.

I've left mine plugged in overnight and had no problems.

 

Mine shuts off automatically. I think it only takes about 20 minutes.

 

Im not even talking about the unit power, the cable itself. I want to leave the cable plugged in and tucked away so I can scan it whenever (been doing it alot lately). I figured it was just coincidence, just needed some backup, thanks guys.

 

Don't leave the auto XRay in the hot car.. I learned the hard way that the heat[and I had it covered from direct sunlight] ruined the keyboard..
I tested it and swapped the keyboard with another older one I had and it works again..
I have left just the cable plugged into ALDL port for days, and it had no effect on the car battery..