Ok Led Diagnostics; Troubleshooting Wan Interface Cards And Cables - Cisco 1720 Hardware Installation Manual

Chapter 3 Troubleshooting

OK LED Diagnostics

Number of Blinks
2
3
4
5
6
9

Troubleshooting WAN Interface Cards and Cables

78-5405-03
Power system—Check the external power source, power cable, router power
•
supply, and circuit breaker. Check for inadequate ventilation or air circulation
that might cause overheating.
ISDN configuration—Consider ISDN-specific hardware and software
•
configurations (ISDN BRI WAN interface cards only).
Use the front-panel OK LED to determine any problems with the router. When the
router first boots up, it performs a power-on self-test (POST). If the router detects
a problem during the POST, the OK LED blinks in a different patterns (described
in Table 3-1) depending on the problem. A pattern consists of a specific number
of blinks that is repeated until the router is turned off. If the router experiences
any of these problems, contact your Cisco reseller.
Meaning
The 860T dual-port random-access memory (DPRAM) failed.
The parameter RAM area of the 860T DPRAM failed.
The 860T system protection control register has a write failure.
The router cannot detect the dynamic random-access memory (DRAM).
The user programmable machine has a write failure.
The router DRAM failed.
Use the show diag command to help determine problems with a card.
lists problems that could occur with the WAN interface cards and the possible
causes of these problems.
Table 3-1 OK LED Blinking Patterns
Cisco 1700 Router Hardware Installation Guide
Table 3-2
3-7