The other aerotrain was repaired and put into service at 3.50pm, it added.
The aerotrains are used to transport passengers between the main terminal to the satellite buildings. They had been shut down temporarily due to emergency maintenance works yesterday.
“We had 17 buses and three vans ferrying passengers between the main terminal and satellite buildings to ensure a smooth and quick journey for passengers,” MAHB said.
MAHB also advised passengers to be at the airport early to avoid unnecessary delays since more than 90,000 passengers are expected daily at the airport during this peak travelling season.
Yesterday, it was reported that the aerotrain service at KLIA was down again, causing a delay in travel as hundreds of passengers waited for buses to transport them.
This is the third time a breakdown has occurred this year.
Several videos and photos posted on social media showed the entrance to the trains sealed with tapes reading “Maintenance in Progress”.
In September, MAHB managing director Badlisham Ghazali said the two trains, which had been operating for nearly 20 years, would undergo a major overhaul by the end of the year.
Malaysia Airports to introduce airside transfer at KLIA, klia2