NEC NDA-24300 manual Control System Fault Fault Occurs Intermittently, For Dual Configuration

FAULT REPAIR PROCEDURES

6.2 Control System Fault - Fault Occurs Intermittently

Faulty Situation:

•Fault occurs intermittently at ACT side in the dual configuration system.

•Fault occurs intermittently in the single configuration system.

•[0-C] ~ [0-K] CPU Failure

•[1-C] Both TSW Write Failure

•[1-D] TSW Write Failure

•[3-D], [3-E] Lock-Up Failure (Permanent/Temporary)

ATTENTION

Contents Static Sensitive

Handling Precautions Required

(1) For Dual Configuration

START

Replace ACT-side related circuit card (CPU, GT, TSW, MUX, EMA) with a spare, and check.

A

When a fault is not indicated, set the faulty system to STBY mode. Refer to Section 12, System Control Pro- cedures, in Chapter 6.

Replace the circuit cards (CPU, GT, TSW, MUX, EMA) individually referring to the following sec- tions in Chapter 4:

•Section 1.3.1, CPR Replacement Procedure

•Section 1.3.2, EMA Card Replacement Procedure

•Section 2.3.1, GT Card Replacement Procedure

•Section 2.3.2, TSW Card Replacement Procedure

•Section 3.3.2, MUX Card Replacement Procedure

Place the circuit card (CPU, GT, TSW, MUX) into ACT mode individually by executing CPU or Speech Path System changeover. Refer to Section 12.1.6, Manual System Changeover of Speech Path System, in Chapter 6.

Check to see if a station-to-station connection can be set up and identify a circuit card responsible for the fault.

After all the steps are complete, place the whole circuit card (CPU, GT, TSW, MUX examined above) to the ACT mode. Refer to Section 12.1.6, Manual System Changeover of Speech Path Sys- tem, in Chapter 6.

Check to see if a fault is indicated.

NDA-24300CHAPTER 5

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