Rubuta ci gaba don wannan sakin layi - A shekara ta 2002, ya yanke shawarar mayar da hankali ga Telefónica World Series, wanda ya lashe. Daga nan aka dauki Zonta aiki a matsayin direban gwaji na kungiyar Toyota F1 a 2003, inda ya ci gaba da aiki a shekarar 2004. Zuwa ƙarshen kakar, ƙungiyar ta kori Cristiano da Matta daga kujerar tsere, kuma Zonta ya tuka a cikin Grands Prix huɗu. A ƙasar Belgium
, yana gudu a matsayi na huɗu a zagaye uku daga gamawa lokacin da injinsa ya lalace. A Suzuka kungiyar ta dauki Jarno Trulli aiki kuma dole ne Zonta ya zauna taron, amma kungiyar ta ba shi damar yin gasa a tseren gidansa, Gasar Grand Prix ta Brazil, wanda ya gama a 13. Ya ci gaba a matsayin direban gwaji na Toyota a 2005, tare da gogaggen matukin jirgin Faransa Olivier Panis. A Babban Prix na Amurka daga baya a wannan shekarar, ya tsaya a matsayin Ralf Schumacher da ya ji rauni kuma ya ɗauki matsayinsa a kan grid, kawai don Toyota, kamar sauran ƙungiyoyi shida na Michelin, don janyewa daga tseren saboda damuwar tsaro. 2006 ya ga Zonta ya ci gaba da Toyota a matsayin na uku da kuma gwajin gwajin. An tabbatar da shi a matsayin direba na gwaji don ƙungiyar Renault Formula One don kakar 2007 a ranar 6 ga Satumba 2006.