Network Router User Manual

1. Check the red alarm LED on the craft interface:
■ If it is lit, issue the following CLI command for information about the cause
of an alarm condition:
user@host> show chassis alarms
For a list of messages that can appear in the output, see “Hardware and
Interface Alarm Messages” on page 80.
A common cause of power supply shutdown is that the temperature of the
power supply or another router component has exceed the maximum limit.
■
If the red alarm LED is not lit, check that the power switch is in the ON
position on the power supply faceplate.
2. Replace the faulty power supply with a spare. For instructions, see “Replacing
an AC Power Supply” on page 107 and “Replacing a DC Power Supply” on page 112.
If the LED lights correctly on the spare, the original power supply is faulty. Return
it to Juniper Networks for replacement, as described in “Contacting Customer
Support and Returning Hardware” on page 189.
3. If the spare power supply also does not work, connect the router to a different
power source. You might also try replacing the power cord (on an AC-powered
router) or power cable (on a DC-powered router). For instructions, see
“Disconnecting and Connecting AC Power” on page 110 and “Disconnecting and
Connecting DC Power” on page 116 (you do not need to disconnect and reconnect
the grounding cable on a DC-powered router).
4. If you cannot determine the cause of the problem or need additional assistance,
see “Juniper Networks Technical Assistance Center” on page 83.
86 ■ Troubleshooting the Power System
M10i Internet Router Hardware Guide