ADTRAN 25 manual Total System Failures, Port Problems

MAINTENANCE

Sometimes, faults recorded in the error log and user-reported troubles will exist at the same time. The logged faults should always be cleared first, if possible. This procedure often clears the user-reported troubles without any additional maintenance.

Clearing the most serious logged fault may clear some or all of the other faults. Descriptions of the errors in the error log section indicate their relative urgency .

Error log records should be manually recorded before clearing a recorded error or alarm. If a faulty CP is located in the process of clearing a problem, it must be replaced with a known good CP. The associated error record should be included with the CP when it is returned for repair. If the SAT has an associated printer, the error records can be printed instead of being manually recorded .

Traditional troubleshooting methods still have a valid place in maintaining a system as advanced as System 25. And sometimes these methods are sufficient to locate and clear faults. These methods include voice terminal substitution, visual inspections, continuity checks, and clarification of operating procedures with users.

Total System Failures

As the flowchart in Figure 4-1shows, a failure of the common control circuitry (that is, CPU/Memory and Service Circu it) must be repaired immediately. This procedure mayclear other problems in the system as well.

Port Problems

Port CP failures can usually be cleared by replacing the CP that has a lighted red LED (if reseating was unsuccessful). When replacing suspected defective CPs, wait until the amber LED (indicating CP is in use) goes dark before removing the pack.

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