Armed with a lush political campaign fund and three of the best lobyists in town, the Association of Trial Lawyers of America is doing battle for the forth time in five years against the no-fault auto-insurance bill.

The stakes are huge. A 1971 Department of transportation study said lawyers pocket about $1 billion a year in fees resulting from automobile injury cases. ATLA President Robert Begam claims the figure is much lower - no more than $300 million a year. That's still a lot.

The association's 34,000 members include lawyers who bring virtually every lawsuit in the nation on behalf of persons injured in auto accidents. The no-fault bill would wipe out the vast majority of such lawsuits and allow an injured person to collect automatically from his own insurance company on most personal injuries. Lawyers would lose: no lawsuits, no fees.

The association though relatively small, has shown lots of political clout in combats over no-fault. Lawyers are educated good speakers often influential in local politics and in this battle would appear to be highly motivated.

Last year ATLA's political campaign fund (called Attorneys' Congressional Campaign Trust) collected $439.000 in voluntary contributions from lawyers and ladled out $315.000 to members of Congress in campaign donations while using $79,000 for operating expenses. So far this year it has accumulated $128,000. Though technically separete, the fund gives money to the people ATLA likes, Begam said.

Its roster of recipients looks like an honor roll of the House Commerce Committee, which has jurisdiction over the no-fault bill plus a quarter of the Senate and many other House members:

Rep. John E. Moss (D-Calif.). second-ranking House Commerce Democrat House Minority Leader John J. Rhodes (R-Ariz.) Nearly ever Republican on the Commerce Committe and almost half the Democrats. Senate Majority Leader Robert C. Byrd (D-W.Va.). Eleven of the 18 new senators - getting from $1.000 to $10.000 apiece. Sen. Donald W. Riegler Jr. (D-Mich.) $10.000. Sen. Malcolm Wallop (R-Wyo.), $1,000 only a few weeks ago. Sen. Edward Zorinsky (D-Neb.). Sen. James R. Sasser (D-Tenn.). Sen. Orrin G. Hatch (R-Utah). Sen. H. John Heinz III (R-Pa.). Sen. John Melcher (D-Month.) - the list goes on an on.

Last years and this year ATLA has retained the services of three of the best-connected and most effective lobbyists in town. One is Tom Boggs, who has grown up in Washington politics and handles most ATLA business here. His father was the late House Majority Leader Hale Boggs (D-La).

His mother, Lindy Boggs, (D-la.) now has her husband's former seat - and incidentally received $500 last year from the campaign fund.

William Timmons and Tom Korologos are ATLA's two other top lobbyists. Timmons was the chief of congressional liaison in the Nixon-Ford administrations, and Korologos the top Senate lobbyist for the White House. Now they have a firm that specializes in lobbying for hire.

Three times since 1972 the trial lawyers have beaten congressional passage of the no-fault bill - by a 49-to-46 Senate vote in 1972, by House inaction in 1974, and by a 49-to 45 Senate vote last year.

This time ATLA will find the going rougher. Sen. Warren G. Magnusion (D-Wash.) is pressing eagerly for passage. President Carter has endorsed the bill, the first time it has ever had administration backing. Transportation Secretary Brock Adams, a close friend and Washington state political ally of Magnuson, he said he'll go all out for it.

And former Magnuson aid Lynn Sutcliffe, now in private law practice, who worked on the bill when he was a staffer on the Commerce Committee, is headling a committee for customers no-fault that includes big unions consumer groups and some big insurance firms who have come over to the no-fault idea.

A classic lobbying battle pitting the trial lawyers against the Sutcliffe group and the White House is now in prospect.

Under the no-fault concept, which all states would be required to put into effect for auto insurance within three years, a person injured in an auto accident wouldn't have to obtain a lawyers and sue to collect compensation for most medical bills, loss of pay nursing care and other personal-injury costs arising from the accident. Instead, he would be paid automatically by his or her own insurance company regardless of who was at fault, up to certain limits - for example. $100,000 for medical and rehabilitation costs.

The victim could sue for additional damages only if killed, disfigured, lost a physical functions or became disabled for a long period or permanently. The theory is that by eliminating costly lawsuits to collect in relatively minor accidents, hundreds of millions of dollars now going into lawyer fees could instead be channeled to benefits.

Government figures indicate that 44 cents of every insurance preminium dollar goes to benefits and nearly 20 cents to legal costs. Proponents say no-fault could shift a significant portion of the 20 cents paid for legal fees onto the benefit side, resulting in more (and quicker) compensation to injured persons.

ATLA President Begam said the loss of income to lawyers isn't really the issue. "The idea that lwayers have a billion-dollar stake in this, that's a joke," he said in a telephone interview from Phoenix.

"We're against no-fault because it is mandatory, compulsory accident and health coverage . . . in exchange for which the American driver is asked to give up his right to trial by jury when he's hurt. Ninety-six per cent of all people who are injured will lose their rights to go to court - those who are paralyzed and brain-injured can still go to court. Sutcliffe brags about the fact that this will eliminate 96 per cent" of all potential personal injury suits.

Begam contended that the bill could conceivably eliminate lawsuits for damages for ruptured spleen, facial scars, even loss of fingers, "unless you're talking about t touch typist or Jascha Heifetz or Arnold Palmer . . ."

Sutcliffe responding to Begam in an interview, denied using the 96 per cent figure in application to the current bill, but said. "The vast majority of suits are unnecessary. We're eliminating the right to sue [for relatively minor injuries] and giving them the right to be compensated.

"We think the Transportation Department is correct in estimating $1 billion or more for lawyer fees and even if it were only $300 to $400 million, it's still to much. That money should be going to the victims, not to trial lawyers." He added that contrary to Begam's assertions, the bill would leave it to a jury to decide whether added compensation should be paid for scars, permanent loss of a finger or loss of spleen.

The trial lawyers are planning a heavy lobbying and informational campaign to kill the bill once again.

Begam said political contributions to members of Congress are made by the trustees of the campaign trust on a general review of a candidate's record and view and not solely on how they thought he would vote on no-fault. "Unfortunately we are perceived as a one-issue organization, but clearly we're not," he said. "For example, we are lobbying for the consumer protection act and national health insurance." He said many of the ATLA members are liberals and many are labor as well as negligence lawyers.

Begam said his organization intends to lobby by every method and in every location. "We use personal contact, mail, phone, you name it. If we want to lobby a senator from Mississipi our Mississippi group usually does it."