I like using an Elm327 OBD II code reader, but the port location below the steering column leaves it prone to bumping and the reader is easily forgotten (where it can continue to draw current).
I purchased an OBD extension cable that has a right angle connection and it works great. The cable sits nearly flush with the trim, and I can route the cable behind the steering column and out just below the gauges. I keep the extra length neatly coiled behind the dash, but use that extra length if I need to log data on the computer.
Available on Ebay, Amazon etc. make sure you get the right angle connection if you want it to be low profile.