His career dates back to 1984, as the co-host of Emotion 98.3. He originally shared the show with Lionel Makepeace, who was often at odds with him and did not understand Fernando's poetic monologues about passion and lust. He hosted the show himself by 1986. Martinez also does commercials for Medallion Man in Vice City.
He was forced out of Vice City for unknown reason, and moved to San Andreas where he became the improvised host of Lonely Hearts on WCTR in 1992.
In Grand Theft Auto III, he runs a program called Fernando's New Beginnings, where husbands relieve the stress of married life by getting a mistress. He is interviewed on Chatterbox FM by Lazlow - when asked about his background, he says he is "Latin" but later admits that he is from Upstate Liberty. Lazlow ends the show by yelling "You're just a cheap pimp from Upstate, get out of my studio!".
In 2008, he is the host of Episodes from Liberty City exclusive radio station Vice City FM. He admits that he has several children, he is a registered sex offender not allowed within 200 yards of a school, and has a sexually transmitted infection.
Fernando is once again heard on radio in Grand Theft Auto V, where he is seemingly trying to give up his womanizing ways and trying, though very frequently failing, to respect women and treat them as something more than just sex objects.
"I have worked in a lot of radio stations, but Vice City FM really makes the ladies wet. Fernando loves an '80s slut - not too much hair downstairs, comprendez? Don't give up the dream, Fernando will take you back."
"You know, Liberty City used to be a lot more fun. In the old days, you could fill your nose full of powder, and your loins full of passion twenty four hours a day. A man could beg, borrow, and steal his way to a fortune, and be loaded for it. Now, the place is run by robots! No longer can a wise man bring to his fellows the joy of partnership - the beauty of love. People, they call me dirty words - words like 'pimp' and 'statutory rapist', but I say you are beneath me. I, Fernando Martinez, am not about nostalgia. I am not a freak show, playing to your memories of better times. I am the American Dream - a self-made man bringing happiness ... capturing fire."
"There are many politics of dancing - this is Re-Flex."
"Ooh, I am Wet Wet Wet for this song..."
"This is Texas, with 'I Don't Want A Lover'. What's wrong with you, Texas, are you gay?"
"Robbie Nevil, give us that French song 'C'est la vie'!"
"Fernando wants to be your Cuddly Toy, amore."
"What do you do when the passion becomes so intense that the woman's water breaks? Take it from Fernando - call a taxi, because when the husband finds out, you are in a lot of trouble."
"From time to time, people come to the radio station and say 'I am looking for my papa Fernando'. I say 'I am sorry, but your father - he is dead. I am just the janitor.'
"What is romance? What is passion? Maybe a sexy t-shirt that says 'Cunnilingus Instructor'. Maybe it is the mudflaps on your truck, with the silhouette of the naked lady. People ask me 'Is it better to be a DJ or a saviour?' I have been both, and trust me, both have their benefits. Now, we remember the great music of the 1980s. You may not believe this, but we did not have the internet then. When you found a magazine with the pictures of the naked ladies, it was heaven! The promised land! You hide it. Your mother comes into the room without knocking, and you are working yourself into a froth. This - this is the American childhood I longed to have, and it is how I have raised my sons."
"Fernando loves it when a boy meets a girl. This is 'Waiting For A Star'."
"Can you believe this? Women's rights? What about women's wrongs? Fernando knows that when a woman says no, she is very wrong."
"Fernando has a lot of viruses on his laptop - it burns. He is going to call up Tech Support and make the phone sex with the lady, then maybe she will send me a new one."
"Commercials are all we have left in the world - that and swine flu from having sex with a fat woman."
"You want a commercial? No? Tough shit, buddy. Sponsors and payola are how Fernando makes money."
"Fernando was surprised to discover that in this country they allow women to vote! Incredible! Can you believe it? A creature as delicate and enticing as a woman allowed to make decisions? For me, a woman has only one decision - front or back. Politics, like hunting, like showering, is for men. Women take baths, and think about puppies, and amore. My women never vote - this is why I keep them illegal."
"Maybe you think the government is spying on you. They know of the little latina you have been text messaging, saying you are rock hard, with passion. Then you realise you have text messaged the wrong person. Now your best friend thinks you are gay. Life is full of surprises!"
"You realise how old these songs are - how old you are. Your life is nearly over, Fernando's is just beginning ... again ..."
"This is a request from my woman in Bohan. She says 'Find The Time'"
"I hope you are with a lady this afternoon, even if you are a lady. This is passion."
"Good morning, Alderney. Fernando would like to apologise for what he did on the bridge last night. I was very drunk."
"And remember, the passion. She is back on the Fernando Show."
"Fernando became an American the courageous way. By outrunning the speed boat."
"A powerful bear who loves his honey."
Fernando Martinez has almost been heard in all the 3D Universe games and the HD Universe games, only to be beaten by Lazlow.
It is unknown if Fernando is related to Jerry Martinez, because they have the same last name. It's highly unlikely however.
Fernando is the only fictional DJ to appear on GTA IV and its add-ons.
Fernando has a habit of referring to himself in the third-person and constantly flirts with women he talks to.