Code u0100 and u0101 2008 aveo - 2008 Chevrolet Aveo

U0100 is lost communication with the PCM (on board computer that controls everything) the U0101 is no communication with the TCM (transmission Control Module. I have read where a lot of people have had no luck trying to fix this and the delaers charge big bucks for it. typically the problem starts shortly after being jump started or having to jump start someone else and hooking the cables up properly. it can also just happen over time which is another of the many reasons i hate new cars. one fix i saw was to remove the positive battery cable and let it sit for 15-30 minutes then ground the positive cable out for 20 seconds before reconnecting it to the battery again, this may not work and if it doesn't it will require either the TCM be replaced or the dealer to have to dig into your car and charge you big time for the work. hope that helps

little side note i have seen some of these error messages cleared up by cleaning up the ground contacts for the TCM and even one fella had some luck replacing the speed control sensor in his and the lights all went away and it ran fine after that.