The direct train from Chennai Central metro to Airport metro, the green line of the Metrorail, was affected the entire Tuesday due to point machine failure, said Chennai Metro Rail Limited (CMRL) officials.

A day after the service was stopped, the CMRL posted on X at the commencement of operations on Wednesday that the direct train service between Chennai Central metro to Airport metro (Inter-Corridor) have resumed normal operations.

Explaining the reason why it took a day to rectify the problem, a CMRL official said the technical snag pointed to the failure of the point machine that allowed crossing of trains from the green line (Corridor 2) to the blue line (Corridor 1). Replacing the point machine during daytime would have disrupted the services on the blue line also, at least for more than one hour.

“This would have resulted in no trains being operated to the Airport during this period, causing even more inconvenience to the commuters. So, we had to wait until night to repair the point machine,”the official said.

Another source in the CMRL said that they had tried taking up repairs in the morning itself when the technical snag was identified. The point machine had a mechanical failure, a one in a million hours failure. But since that could not be done, the machine was replaced at night after services ended, he said. All the point machines are checked routinely for problems, the official added.