Hardware Troubleshooting 5-9
Troubleshooting the Cooling Subsystems
—Verify that the overtemperature LED is off.
If a power supply overtemperature LED lights , v eri fy that the ambien t tem perat ure is belo w
120°F (50°C) and the air intake is not blocked. If the condition persists, replac e the power
supply.
—Verify that the current limit LED is off.
If a power supply current limit LED lights, ver ify that the DC b u s ter minals on the AC-input
power shelf rear are not short-circuited and a supported dial shelf conf iguration 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 acces s server
can operate in temperatures of up to 120°F (50°C) for a maximum of 7 2 h o u rs. 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 fa ilure. Both the router shelf fan
tray and the dial shelf blower assembly c an be removed and replaced while the system i s 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 , lis ten for the m. In noisy en viro nments,
place your hand on the left side of the router shelf (when viewi ng t he route r 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 f ans o r there is a problem wi th t he po wer to t he
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.