After reaching one million kilometers, each AS-2002 of Santiago's Metro is submitted to the deepest technical inspection. In this inspection, trains are almost completely disassembled and a large amount of mechanical parts are replaced.
In the image, unit 444 is undergoing maintenance. Bogies have been removed, in order to disassemble them, so that wheels can be replaced by new ones and perform the necessary maintenance to the engines and brake discs.
Doors were removed also, to clean them and also to inspect the opening and closing mechanisms.
Photo taken with permission