The Ministry of Defence has admitted that a fault at a radar dome was responsible for causing electrical problems with dozens of cars.
The MoD said there had been no known recurrence of the problem
Engines and lights cut out and speedometer dials swung up to 150mph as motorists drove past the dome.
At the time the MoD said there was no guarantee that the Trimingham radar on the north Norfolk coast was the cause.
It now says it will consider claims for compensation after an inquiry found the radar was "out of alignment".
An MoD spokeswoman said the inquiry revealed the Type 93 radar spinning inside the dome had been out of alignment between November last year and this February.
The spokeswoman said that there was no danger to the public or personnel but the MoD would now consider outstanding compensation claims on a case-by-case basis.
Neil Crayford, who runs the nearest garage, Crayford & Abbs at Mundesley, said he dealt with 30 calls over a couple of months.
He said the problem was still happening.
"We have had a Nissan Terrano in here three or four times in the past week with the same sort of problems - dials going haywire and blacking out, which we had to reset."
But the MOD spokeswoman said: "There is no known recurrence of the problems experienced last year."