Filter
Top Products
vii
Cisco 1750 Router Hardware Installation Guide
78-6169-02
Problem Solving
• ISDN configuration—Consider ISDN-specific hardware and software
configurations (ISDN BRI WICs only).
OK LED Diagnostics
Use the front-panel OK LED to help 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
pattern (described in Table 1), depending on the problem. A pattern is 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.
Table 1 OK LED Blinking Patterns
Number of Blinks Meaning
2 The 860T dual-port RAM (DPRAM) failed.
3 The parameter RAM area of the 860T DPRAM failed.
4 The 860T system protection control register has a write
failure.
5 The router cannot detect the dynamic RAM (DRAM).
6 The user programmable machine has a write failure.
9 The router DRAM failed.