• Supported Platforms
• T1600 Routers

• Related Topics
• Replacing T1600 Cooling System Components
• T1600 Cooling System Description
• T1600 Chassis Description

Troubleshooting the T1600 Cooling System

Problem

The following alarms, LEDs, and other conditions indicate a problem with the cooling system:

• A red alarm indicates that temperature of the router exceeds the maximum (“temperature hot”) threshold.
• Automatic shutdown of the power supplies was caused by the temperature of the router exceeds the maximum (“temperature hot”) threshold. The control board turns off the power supplies because the router temperature exceeds the acceptable maximum.
• A red alarm indicates that a fan failed.
• A yellow alarm indicates that the router temperature exceeds the “temperature warm” threshold (yellow alarm).
• A yellow alarm indicates that one of the fan trays was removed.
• One or more fans in a fan tray function at full speed.

During normal operation, the fans in each fan tray function at less than full speed. The control boards constantly monitor the temperatures detected by sensors on the midplane and router components, adjusting the speed of the fans as necessary.

Solution

To troubleshoot the cooling system:

1. 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.
2. 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.
3. 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.
4. 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

   For information about the alarms, see Table 1.