OBDII

I bought an ELM327 for $12 on Amazon to use with Dash Command in my R56. (The purple-and-gold labels on the OBDII units have different brand names, but they all seem to be the same inside.) The only other things I remember that you need to watch out for are Apple vs. Android - and WiFi vs. Bluetooth, depending on what devices you're running. Oh, and these suckers run really hot and suck a lot of juice if you leave them plugged in when your engine's not running; they can drain a battery overnight.

 

^^ agreed with the above comment. I bought this one and works great with my iPhone on R56:

ELM 327 Wi-Fi OBDII

 

I got one of these last year and had to add an adapter cable to get it tucked away so that I would not knock it loose with my left leg. Extender cables for OBD2 are $5 on ebay

I run Torque for Android on it with 4 displays and the data rate is fine to keep all those going.

 

really, nobody makes one that auto shuts off?

 

Interesting.
I have both an elm BT device and torque and also a scangauge.

I never noticed the elm drawing power or being hot, but I never touched it to find out.

I use the scangauge all the time and it doesn't show that it is drawing power when the car is off.

Never had a battery get killed by either.

 

Maybe it's a second-generation thing.

 

I don't leave mine plugged in - but I mostly use it for diag purposes only, not daily logging or monitoring.

 

Maybe I may be mistaken what you are asking for but I use an Ultra Gauge. It will read most all the PIDs from the diagnostic connector, clear DTC's and also check in the readiness area for emission testing. It will not log though.
http://www.ultra-gauge.com/ultragauge/
You can see it on my thread.

http://www.motoringalliance.com/forums/mini-stuff/24721-09-pepperwhite-toy-dd.html#post319241

 

https://www.scantool.net/obdlink-mx.html

" its BatterySaver™ sleep mode allows the adapter to stay plugged in continually, without draining the vehicle’s battery."