Will it flatten the battery? I'm using it so often I don't want to damage the plug/socket...

I know the LEDs stay on on some Elm OBD 2 stuff with ignition off.

 

Great question... I have a small electrical discharge that completely depletes the battery if I don't drive it for a week or more.

I also leave the cable in all the time, and suspected that it was the problem.

Sorry that I did not answer your question, but knowing that your not is the same boat sometimes helps.

 

I'd look for a recent install as the culprit. Did you do a wideband?

 

There can be a small amount of current that can be flow. I think it is not much, but I don't know how much it really is.
The +12V drive the LM555CM IC permanently. The datasheet of the 555 says that with no load the maximum current is 15mA.

 

I'll probably leave it plugged in then except on holidays.

 

Mine is always plugged in since I am almost always logging data from the ECU. My battery has suffered no ill effects.

 

I had mine in for a week with no effects.

 

Yes, it draws a VERY small amount of power, however the evo has a power management module that shuts power off to the port after 15-20 minutes.

The current drawn by an aftermarket radio's clock circuit draws way more current, not to mention it maintains a constant power where most everything else gets shut down.

If you left your headlight, interior lights on for any period of time it shuts down on its own after 15-20 minutes of the power being off and the doors locked.

 

I leave mine plugged in all the time as well.

 

mine never comes unplugged w/e of flashing another car.

 

it is similar to leaving the Creader plugged in. How come the Creader doesnt turn off? It keeps blinking even after 20 min