Internal Affairs cops got a big break in their exploding ticket-fixing probe when they caught a Bronx sergeant shamelessly trying to make a traffic violation disappear for an honorary NYPD deputy commissioner, The Post has learned.

The incident shed light on the widespread practice of cops quashing tickets for big shots, sometimes at the orders of their superiors.

Early last year, police-connected businessman Albert Thompson — who shares his deputy-commish title with celebs like Donald Trump and rubs shoulders with top brass, including Commissioner Ray Kelly — called his buddy, Sgt. Keshawn Hickman, saying he needed to get rid of a moving violation.

Hickman found out the ticket was already being heard in Bronx traffic court, and allegedly dispatched two rookies to take care of the problem.

“He told them to go down to traffic court and see officer so-and-so and have him take care of the ticket and say it’s for the chief so-and-so,” a source said.

That officer would then make up an excuse to the judge why the ticket should be voided, and the problem would be solved.

But the plan quickly unraveled when the cops sent to the courtroom started wandering around like lost puppies and drew the attention of a sergeant who was not in on the scheme.

“A sergeant comes up and says, ‘Can I help you?’ and they say they’re there to take care of this ticket, and the sergeant says, ‘What?’ and he reports them to IAB,” the source said.

When the unidentified chief learned of the plot, he said he’d never heard of Thompson — and Hickman was yanked from his cushy post at Bronx Borough headquarters near Crotona Park to the 41st Precinct near crime-ridden Hunts Point.

It’s unclear what happened to the rookies, who spilled details of the plan to the IAB investigators.

Police conversations about this ticket-fix incident were later caught on wiretaps set up as part of the larger probe that began in 2008.

A source said the example proves that the fixing epidemic “is not a union issue, it is a job issue coming from all ranks, even much higher than sergeant.”

As many as 400 cops — most of them assigned to 12 Bronx precincts — could face departmental charges for allegedly fixing tickets. If found guilty, they could be fired, lose benefits or be reprimanded.

And Bronx DA Robert Johnson has convened a grand jury that is weighing criminal charges against another 40 officers accused of taking bribes for fixing tickets for relatives and friends.

At least one Yankee executive saw his ticket go away, The Post has learned.

READ MORE: NY POST