Alstom is working to resolve the problems affecting the REM

An aerial view of the REM train travelling from Ile Bigras on the Deux Montagne line in Laval, Que., on Friday, Dec. 12, 2025. THE CANADIAN PRESS/Christinne Muschi

The company responsible for Montreal’s light-rail (REM) trains has promised to implement solutions after acknowledging that its service has been unreliable since the opening of a new branch line last November.

Alstom Canada says it has identified faulty electronic components as the cause of many recent disruptions affecting the network.

In a statement, the company said it expects to complete repairs in the coming days.

It admits that service has fallen short of expectations, with frequent delays, particularly on the 30-kilometre extension of the REM, which opened on Nov. 17 and connects Gare Centrale (Central Station) in northwest Montreal via Laval to Deux-Montagnes.

Quebec Transport Minister Jonatan Julien said the situation is unacceptable and that he has had numerous discussions with CDPQ Infra, the network owner, Pulsar, the operator, and Alstom.

“I expect an improvement in service reliability for users,” he added on social media.

- This report by The Canadian Press was first published in French on Jan. 30, 2026.