After an operation to remove vocal cord nodules in 1977, she was ordered to rest her voice. But one day she screamed in anger, permanently altering it.
Six years on, the Welsh singer would release her best-known song, Total Eclipse of the Heart, which flaunted her husky sound and was nominated for a Grammy Award.
Holding Out for a Hero, another dramatic rock ballad, was released soon after, helping Tyler make her mark on Britain's pop scene.
Both recordings have since featured in films, television shows and advertisements.
Tyler, whose releases also included It's a Heartache and Lost in France, died "unexpectedly" in hospital in Portugal where she was being treated for an illness, according to a statement on her website on Thursday. She was 75.
Tyler was born Gaynor Hopkins in south Wales in 1951, the fourth of six children of a coalminer and a homemaker.
She grew up in a four-bed council house with a large garden in the village of Skewen, outside Swansea.
"I think mam and dad had it really hard, bringing up a big family on very little," she told The Guardian newspaper in 2012.
Music was a constant of daily life, whether played on a radiogram or sung by her mother, who would intone opera or Itsy Bitsy Teenie Weenie Yellow Polkadot Bikini as she did housework.
At seven, Tyler went to see a musical at the local church. There she fell in love with Irving Berlin's song There's No Business Like Show Business, first giving the shy child the desire to perform.
"I wouldn't say boo to a goose, and yet there was a part of me that yearned to sing in front of people," she recalled in her memoir, Straight from the Heart.
She started out as a teenage backing singer before releasing several albums of her own in the 1970s.
But it wasn't until the early 1980s, when she started working with American lyricist Jim Steinman, that she had her commercial breakthrough.
She won over Steinman, then already famous for composing Bat out of Hell for Meat Loaf, by sending him demos of the theatrical rock songs she knew would suit her voice.
Of the moment she first heard his composition, Total Eclipse, she recalled: "I knew this was the song I had been waiting for all my life."
Recorded by Tyler for her fifth studio album Faster Than the Speed of Night, the Wagnerian-like onslaught of sound and emotion, as Steinman described the piece, would go on to top the charts in the UK, US, Australia and New Zealand.
Featuring the powerful lyrics "Once upon a time, I was falling in love, But now I'm only falling apart", the song has been streamed more than one billion times on the online music platform Spotify.
It has featured in the movies Old School and Bandits, the television shows Glee and Grey's Anatomy, as well as an advertisement for Mastercard.
The music video, a staple of early-days MTV, was shot in a frightening gothic former asylum in Surrey.
The visuals included slow-motion tossed doves, candles, dancing ninjas, dancing greasers, Tyler in big shoulder pads, fencers, gymnasts, wind machines and shirtless boys wearing swim goggles being doused with water.
Faster Than the Speed of Night earned a Grammy nomination for best rock vocal performance - losing to Pat Benatar's Love Is a Battlefield - and Tyler got another nod for Total Eclipse in the best pop vocal performance category, losing to Irene Cara's Flashdance - What a Feeling.
From the 1990s onwards, she had more success in Norway, Austria and France than at home, although she represented Britain in the 2013 Eurovision Song Contest - where she came 19th - and was made a Member of the Order of the British Empire, for services to music, in 2022.
The star continued to make music and perform until her death, having released her 18th studio album The Best Is Yet To Come in 2021.
Tyler married property developer Robert Sullivan, her first serious boyfriend, in 1973.
"I am still very much in love with him and he with me," she said 40 years later. The couple did not have children.
Tyler never really liked her birth name. Asked how she arrived at her pseudonym, she told BBC Radio Wales: "I got a broadsheet newspaper and I made an effort to write all the first names I came across on one list and all the surnames on another and I went through them both and came up with Bonnie Tyler.
"And it's been a brilliant name."
with AP
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