Network Card User Manual
Hardware Troubleshooting 5-9
Troubleshooting the Cooling Subsystems
— Verify that the overtemperature LED is off.
If a power supply overtemperature LED lights, verify that the ambient temperature is below
120
°F (50°C) and the air intake is not blocked. If the condition persists, replace the power
supply.
— Verify that the current limit LED is off.
If a power supply current limit LED lights, verify that the DC bus terminals on the AC-input
power shelf rear are not short-circuited and a supported dial shelf configuration is being used.
Note The dial shelf power subsystem supports a maximum configuration of 10 modem cards.
Troubleshooting the Cooling Subsystems
The Cisco AS5800 is designed to minimize problems in the cooling subsystem. The access server
can operate in temperatures of up to 120
°F (50°C) for a maximum of 72 hours. The access server
also contains rendundant fans in both the router shelf fan tray and the dial shelf blower assembly,
which allow the system to continue operating despite a single fan failure. Both the router shelf fan
tray and the dial shelf blower assembly can be removed and replaced while the system is operating,
provided the procedure does not exceed 1 min.
Router Shelf Cooling Subsystem
In the router shelf, check the following to help isolate a problem with the cooling subsystem:
• When you start up the system, do the router shelf fans operate?
To determine whether the router shelf fans are operating, listen for them. In noisy environments,
place your hand on the left side of the router shelf (when viewing the router shelf from the front)
to feel for air being forced out the vents.
— If yes, power to the fans is good.
— If no, there is a problem with the router shelf fans or there is a problem with the power to the
fan tray.
If you determine that the power supply is functioning normally but a fan is faulty, you can
replace the fan tray without powering off the access server. Contact a customer service
representative if you need assistance.
For problems with the system power, refer to the section “Troubleshooting the Power
Subsystem” in this chapter.