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Cisco MWR 1900 Mobile Wireless Edge Router Hardware Installation Guide
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Appendix A Troubleshooting
Problem Solving
Troubleshooting the Power and Cooling Systems
Both the power LED and the fans can help you troubleshoot a power problem. Check the following items
to help isolate the problem:
Check the following items to help isolate problems with the power supply installation:
•
With the MWR 1900 router connected to the power source, is the power LED on the front panel on?
–
If not, check the DC input, DC source, and the power supply wiring.
–
Check the power supply connection to the motherboard.
–
If the power LED is still off, the problem might be a power supply failure.
•
Does the router shut down after being on a short time?
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Check the fans. If the fans are not working, the router will overheat and shut itself down.
–
If the fans are not working, check the power supply connections to the fans.
–
Ensure that the chassis intake and exhaust vents are clear.
Check the environmental site requirements in the “System Specifications” section on page 1-6.
•
Does the router partially boot, but the LEDs do not go on?
–
Check for a power supply failure by inspecting the power LED on the front panel of the router.
If the power LED is on, the power supply is functional.
–
If the power LED is not on, refer to the
Cisco Information Packet
for warranty information or
contact customer service.
Environmental Reporting Features
The MWR 1900 router has a temperature sensor to detect over-temperature conditions inside the chassis.
The over-temperature detection trips at 75°C +/- 5%. This condition is reported to the processor as an
interrupt and software then takes action on this interrupt to generate the appropriate alarming. If the
router reaches a temperature of 90°C, the power supply will cycle to prevent the box from exceeding that
temperature in a powered up state.
If the router is operating at an abnormally high temperature, you see the following message on the
console screen:
%SYS-1-OVERTEMP: System detected OVERTEMPERATURE condition. Please resolve cooling problem
immediately!
Some causes of abnormally high router temperature are:
•
Fan failure
•
Air conditioner failure in the room
•
Air blockage to cooling vents
Take steps to correct the problem. For information about environmental operating conditions, see
“System Specifications” section on page 1-6.