Washington (CNN) Barry Coates, the U.S. veteran who became the human face of the Veterans Affairs scandal over delays in care in 2014, died on Saturday of the cancer that wracked his body after waits for medical care at a VA facility. He was 46.

Coates became a national figure representing delays in medical care at VA hospitals after he was featured prominently in a CNN investigation in January 2014.

The CNN investigation that included Coates was the first national story about delays in care across the country that year. It led to a national controversy resulting in the resignation of VA Secretary Eric Shinseki, and ultimately a law that provided $16 billion to overhaul the Department of Veterans Affairs, passed by Congress and signed by President Obama.

After the CNN story about him, Coates was asked to testify before Congress about the delays in his medical care. When he got to Washington, Coates told lawmakers he had suffered for months, waiting for a simple medical procedure that might have saved his life.

Coates testified he was dying of cancer because the procedure was delayed at several VA facilities, including the William Jennings Bryan Dorn VA Medical Center in Columbia, South Carolina.

Leaving some lawmakers in tears and making national news again, Coates described in detail how he waited months, even begging for an appointment to have a colonoscopy. But he found himself on a growing list of veterans also waiting for appointments and procedures.

About a year after first complaining to his doctors of pain, Coates said, he was able to get a colonoscopy. Doctors discovered a cancerous tumor the size of a baseball. By then he had Stage 4 cancer, and it was only a matter of time before he was overtaken by the illness, he told lawmakers.

From his first interview, Coates, a simple but articulate man from rural South Carolina, spoke eloquently about how veterans should be treated better, and deserved more after all the sacrifices they had made for their country.

"Due to the inadequate and lack of follow-up care I received through the VA system, I stand before you terminally ill today," Coates told members of the House Committee on Veterans' Affairs.

The lawmakers who heard him testify were shaken by his description, and about the numerous deaths of other veterans outlined in CNN's investigation.

"This is an outrage! This is an American disaster!" Rep. Jackie Walorski, an Indiana Republican, nearly screamed, her voice quavering, during that congressional hearing, in April 2014. "My dad was a veteran. He died of colon cancer," she said, crying softly. "This is so personal to me."

Coates remained friendly and kind, was never hostile, and even kept his humor as his illness progressed. Speaking with his down-home and polite country manner, the Army veteran had a remarkable ability to touch many people with his story.

Coates' family said he died Saturday from the cancer that had been left untreated by the VA for so long. After his time in the national spotlight, Coates continued to rail against the VA and fight for veterans to get better treatment, continuing to speak with reporters and helping them understand the VA crisis and scandal as it unfolded.

Coates' son, Shane, 23, on Wednesday described his father's fight and how he remained committed to helping other veterans to the end.

"Everything they did at the VA was dragged out, it was never a quick appointment for anything," Shane Coates said. "He had to wait so long to get any treatment. After what happened to him, he just wanted to fight for other veterans."

"He wanted to show the world that when you go fight for your country, it's not right that you come home and then you have to fight just to get basic medical treatment," Shane Coates said. "The way they treated him, and other veterans, it's just not the way any veteran should ever be treated. It's just not right."

Coates was buried Wednesday in Bethune, South Carolina, after a service at the Timrod Baptist Church. In addition to Shane, Coates is survived by his father, Barry Coates Sr.; his wife, Donna; his brother Randall; his sister Dawanna; and by four other children: Scotty, 25; Breanna, 24; Troy, 22; and Tyler, 16.