5-8
Cisco ASR 903 Router Hardware Installation Guide
OL-25178-05
Chapter5 Troubleshooting
LED Summary
Note USB TYPE-A receptacle used.
Note The USB flash/MEM port +5VDC is output. We provide power for USB flash/MEM, and it
operates as a USB host device.

Fiber-Optic Specifications

The specification for optical fiber transmission defines two types of fiber: single-mode and multimode.
Within the single-mode category, three transmission types are defined: short reach, intermediate reach,
and long reach. Within the multimode category, only short reach is available. For information about
optical SFP modules, see the documentation for the SFP module at
http://www.cisco.com/en/US/partner/products/hw/modules/ps5455/prod_installation_guides_list.html.
LED Summary
The following sections describe the meanings of the LEDs on the CiscoASR 903 Router.
RSP LEDs, page 5-8
Interface Module LEDs, page5-9
Power Supply LEDs, page 5-12
Fan Tray LEDs, page5-13
Alarm Conditions, page5-13

RSP LEDs

Table 5 -12 summarizes the RSP LEDs.
Note A major alarm condition indicates the failure of a single fan in the fan tray; a critical alarm
indicates the failure of multiple fans. In the event that a single fan fails, the
Cisco ASR 903 Router software adjusts the fan speed to prevent excessive heat within the
chassis.
Table5-11 Single USB Flash/MEM Port
Pin Signal Name Direction Description
A1 Vcc +5VDC (500mA)
A2 D- Data -
A3 D+ Data +
A4 Gnd Ground