Indonesian investigators on Tuesday said a chronically faulty component was the major factor in last year’s crash of AirAsia flight QZ8501.
They also said the flight crew’s unsuccessful attempt to fix the malfunction contributed to the disaster.
The deadly accident killed 162 people in December 2014, after an Airbus A320-200 crashed into the Java Sea.
Contact with the plane was lost 40 minutes into the flight.
The report, which follows a year-long investigation, said cracked soldering on a tiny electronic part in the system was the cause of the malfunction.
Following repeated warnings, the pilots tried to reset the computer system - a method that had been used several times in previous flights.
However, this method disabled the autopilot, causing the pilots to lose control of the plane.
"Subsequent flight crew action resulted in inability to control the aircraft," the report said.
The aircraft then went into a "prolonged stall condition that was beyond the capability of the crew to recover."
According to the report, the same pattern of malfunctioning occurred 23 times in 2014 and maintenance crews were aware of the problem.
AirAsia’s Chief Executive Tony Fernandes thanked investigators on Twitter.
There is much to be learned here for Airasia, the manufacturer and the aviation@ industry. We will not leave (cont) https://t.co/CpqbTh8DWE
— Tony Fernandes (@tonyfernandes) December 1, 2015
Only 106 of the victims' bodies have been found so far.
The majority of the passengers were Indonesian in the flight going from Surabaya, Indonesia to Singapore. There were also a Frenchman, a Malaysian, a Briton and three South Koreans on board.
The wreckage of the plane was found at the bottom of the Java sea near Borneo, days after the incident.