Jimenez started her singing career at the young age of six, on the radio show named El Abuelito welch (Grandpa Welch) with another legendary Puerto Rican show business legend, Jose Miguel Agrelot.
At 15, Jimenez performed the Habanera from Bizet's opera Carmen. Soon after, she joined popular music groups like the Moncho Usera orchestra, and then she released her first album, which contained the hit Tierra Rica (Rich Earth).
During the 1960s, Jimenez became a popular fixture on Puerto Rico's television and enjoyed great renown. She decided then that it was time to internationalize her career and moved to Peru to promote herself in South America. Her stay in Peru, which lasted until 1968, made her very popular among the citizens of that country too. Meanwhile, she kept on releasing albums and scoring more hits.
After she returned to Puerto Rico in 1968, she landed her own section on WAPA-TV's popular lunch-time show El Show Del Mediodia.
During the 1970s, Carmita became a part of the Disco Music movement in her country, and had the number one hit La Generacion De Hoy (Today's Generation), which was followed by La Vida En Rosa, (Life In Pink), a song which was later a hit in English too, Grace Jones performing the English version.
Jimenez began bringing down her yearly number of appearances since 1985, becoming a more private person. In 1994, she participated in a concert named Algo Mas Que Una Cantante (More Than Just a Singer) at San Juan's Centro De Bellas Artes, a concert which reunited many international singing super-stars.
As it turned out, there was a reason for her winding down the number of public appearances each year: In 2002, she announced during an interview with Vea that she had been diagnosed with cancer in 1985. She battled the disease at her home, at the side of her husband, succumbing to it 18 years after being diagnosed.