New to the forum and owner ship, so sorry if this has been covered. I searched and didn't find in the topics, Just bought 2010 hybrid with 31500 miles. Took for smog check and found a cable already plugged in to the OBD port. It's a fairly large electrical cable. pencil size, with a rubber cover. Smog tech disconnected it, said to leave it disconnected, but didn't know what is was for. (BTW, failed smog, because it had been recently battery jump started and not driven far enough to clear 3 codes. Any ideas of what type of equipment or accessories might be left plugged in to this port? The cable goes back up under the dash, but I didn't find what it connects to.