Andrea Moda brought the C4B to the inaugural event of the 1992 season, the South African Grand Prix, held between 28 February and 1 March 1992. On the Thursday before the Grand Prix, an exceptional day of testing was organized for the Grand Prix, which had not taken place since 1985 with the route of the Kyalami circuit substantially amended since. On Thursday morning, during the session in which a driver from each team had to take part, Caffi managed only half a lap before encountering a battery problem which ended his day; Bertaggia did not participate in the meeting as only one car was operational. A press release announced that Andrea Sassetti had sacked a mechanic after he worked on a second C4B chassis against his instructions. However, it was unlikely that two C4B chassis had been shipped to South Africa for the Grand Prix since there was only one Coloni C4 from which only one C4B can evolve. However, the Zurich-based magazine "Motorsport Aktuell" reported that Andrea Moda had taken a second unassembled C4B to South Africa. This hypothetical chassis, if it did exist, may have been an adaptation of the Coloni FC189B.