...and I don't have much to go by, sorry. I watched it been 2001 and 2005.
It's not a mecha, but it's about this male robot whose real appearance is a metallic humanoid frame, but he's able to change to the appearance of a black-haired young man, possibly by holographic means. His friend / companion is a teenage girl, possibly blonde but could also be a redhead. The graphics were cool, late 90s-early 2000s (I'm split between a Warner Bros style like Justice League and an anime with normal hair/eye colors like The Big O).
I can't remember the plot, but the robot had definitely ran away from his creators. There was an episode during which he had been captured and his memory had been wiped clean and the girl had to find him and actually managed to help him retrieve his memory.
I've looked for this cartoon for YEARS! I've easily found other obscure cartoons like Jake and the Wheeled Warriors, Mighty Max and The Bots Master. It probably had only one season because I don't remember watching over 10 episodes.
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