Khalid Baqa, 52, was detained when the Pakistan International Airlines flight from Lahore was diverted from Heathrow to Stansted, flanked by Typhoon jets, in February.
Highbury Corner Magistrates' Court heard on Thursday that the British national was arrested and charged for failing to tell insurance firm Liverpool Victoria that he had been given three penalty points in June 2015 for running a red light, when he later renewed his car insurance.
Baqa, an unemployed former revenue officer at Hackney Borough Council, was jailed for two years in 2013 for possession and dissemination of terrorist material over extremist material found on discs at his home.
Photos posted on Twitter at the time of February's major flight incident over southern England showed several fire engines and a number of ambulances waiting on the ground at the Essex airport.
Stansted is a designated airport for dealing with hijacks and major security alerts and incidents are dealt with in a remote part of the airfield to the north west of the terminal building.
An airline spokesman at the time said UK authorities had "received some vague security threat through an anonymous phone call".
Essex Police said the incident was "not believed to be a hijack situation or terror matter".
No information about the background to Baqa's arrest or whether he was even linked to the flight diversion was given at Thursday's trial.
Police said at the time that he had been due to be arrested anyway when the flight arrived at Heathrow before it was diverted.
Baqa was given a conditional discharge and ordered to pay £115 in costs and victim surcharge after being convicted of fraud by failure to disclose information.
Prosecutor Fabio Vitiello told the court: "The premium would have been £175 higher, therefore the prosecution case is that by not disclosing the conviction he made a benefit for himself by not paying the higher price."
The court heard that Baqa, of Priory Road in Barking, east London, was pulled over on the school run after going through the red light.
As well as the penalty points, Stratford magistrates fined him in June 2015 for not wearing a seatbelt or ensuring his daughter was wearing one in the back of the Renault Modus.
Giving evidence, Baqa said he believed he had not been given the points, only the fine, because it was not mentioned on a court letter he received.
His sister-in-law paid the insurance to allow him to drive around his wife, her sister, who was disabled, he said, and she could afford the higher premium anyway.
He said: "There was no reason for me to be dishonest."
But District Judge Paul Booty said he would have known at the earlier court hearing he had received points as well as a fine.
He told the defendant: "What you have tried to do today is put forward a smokescreen. I don't accept that evidence. Therefore you are guilty of the offence."
Additional reporting by Press Association.