I got my SMG light on my '03 on for the second time in a couple months. Both times it's happened, after turning off the vehicle and letting it sit for a minute, restarting doesn't show the light again.

My question is will the various OBD2 readers (Peake, the ones from Autozone, etc) give codes from SMGII that I can look up in the Bentley manual or do I have to hit the dealer to see if any codes are coming out?

Trying to avoid forking up the time and $$$ for a dealer visit.

I did a search here, but couldn't find any info on SMG code reading.