Tonight, I loaded my truck up with about ~500lbs. of ceramic tile. I turned on tow/haul mode, and started going down the interstate. After a couple miles, the "Service Engine Soon" light started flashing. Nothing seemed to be malfunctioning. I got no error codes (I'm assuming error codes display in the message center). I turned tow/haul mode off, and after a short while, the SES light went off. After I unloaded the tile and restarted the truck, the SES light did not come back on. I anyone has any ideas about this, I would greatly appreciate it.