Troubleshooting the TX Matrix Cooling System

Problem

• A fan fails (red alarm).
• One of the fan trays is removed (yellow alarm).
• The TX Matrix router temperature exceeds the “temperature warm” threshold (yellow alarm).
• The temperature of the TX Matrix router exceeds the maximum (“temperature hot”) threshold (red alarm and automatic shutdown of the power supplies).

Solution

To troubleshoot the fans:

• If the red alarm LED on the craft interface lights, find the source of the problem by looking at the display on the craft interface. The number of alarm conditions, as well as the source of each alarm, appears on the screen.
• Use the CLI to check the status of the fans. For example, you can issue the following command to get information about the source of an alarm condition:
  user@host> show chassis alarms scc

  For information about the alarms, see TX Matrix Chassis Alarm Messages.

• Place your hand near the exhaust vents at the rear of the chassis to determine whether the fans are pushing air out of the chassis.
• If the DC OK LED on one or both of the power supplies is not lit, check the power supply fans to see if they are operating.
• If all power supplies have failed, the system temperature might have exceeded the threshold, causing the system to shut down.
• If the display on the craft interface lists only one fan failure and the other fans are functioning normally, the fan is probably faulty and you need to replace the fan tray.