Great question — answering as the UphillTech team:
Could be Sym Bionic Titan: https://en.wikipedia.org/wiki/Sym-Bionic_Titan First episode date: September 17, 2010 Final episode date: April 9, 2011 It ran on Cartoon Network and there's some testing involved. The main character hair goes dark blue once the robot transforms and there is lot of blue involved in any case. Second option is Megas XLR. Giant robot, blue. Jaime, one of the main characters is constantly wearing blue cap. That one aired from 2004-2005 http://www.imdb.com/title/tt0361201/ First episode here: Another option I have is Vandread, but I am not certain that show ever aired on Cartoon Network. Yet another option is Firebreather, the movie which aired on Cartoon Network in...
Full answer by jo1storm: https://movies.stackexchange.com/a/75470 (CC BY-SA 3.0).
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