NEC nd-20292 manual Section Troubleshooting Flow Charts, Section Self Diagnostics Maintenance

All ports may be checked in software to ensure the

initialization process scanned all hardware correctly. This can be done by displaying the contents of Memory

Block lE-5 on the system programming Terminal.

(Refer to Section 330 for explanation of Memory Blocks.)

After all previous steps have been checked and any

problems corrected, the system programming can be completed. Using Job Specification sheets (supplied in Section 370) helps simplify the programming process.

CAUTION

Ensure the battery switch on the CPU-E ( ) ETU is turned ON.

The next step for the technician is to perform a Second

Initialization (not a First Initialization). Performing

a First Initialization a second time will cause all

programming memory to be lost, whereas the Second

Initialization “cleans out” or “refreshes” the system RAM without any loss of memory.

This completes the installation procedure for the Electra Mark11 System. The technician should check the operation of each Multiline Terminal to ensure the system is working properly.

SECTION 540

TROUBLESHOOTING FLOW CHARTS

540.1 Problem Solving

To find the cause of a problem, first consider all the symptoms carefully. As each aspect of the problem is considered the technician is guided to a probable solution. It is imperative the problem be defined as accurately as possible, so the most efficient steps to a

solution can be taken. The troubleshooting flow charts, in this section, will help define a problem and

direct the technician through the troubleshooting steps.

1.System Down

Although this term is used to describe many conditions, it will only be used in this section to describe one of the following situations:

A.No access to intercom dial tone on any Multiline Terminal or Single Line Telephone installed.

B.No LED indications or no display indications on any Multiline Terminal installed.

C.No system tones are generated.

ND-20292

CHAPTER 5

APRIL.1990

2.Partial Operation

This term will refer to any situation which cannot be completely described under the conditions of a SYSTEM DOWN. (Refer to the index table listing these conditions.)

3.Reset Definition

In the troubleshooting flow charts, the technician is at times directed to reset the station and/or ETU.

A.Terminal Reset - Is accomplished by

unplugging the station line cord from the station and then plugging it back in.

B.ETU Reset -The ETUs are reset by turning the ON/OFF switch on the ETU to the OFF position and then turning it back ON. To give capacitors in the ETU time to discharge, allow some time before turning the switch back to the ON position.

C.Remote Reset - For Terminal Reset use Memory Block 3D4 and for ETU Reset use Memory Block 3D3. Refer to Chapter 3 of this manual.

SECTION 550

SELF DIAGNOSTICS AND

MAINTENANCE

NOTE: Some Self Diagnostics record the time and date of a particular occurrence. Therefore, it is suggested that the system time and date be

programmed prior to any customized programming.

550.1Self Diagnostic Function

The Electra Mark11 CPU automatically checks for hardware and software errors. The detected errors are

stored in the systems memory. This provides the installer or troubleshooter with the ability to retrieve

error information to help diagnose and correct

problems. This is accomplished using a local

programming Multiline Telephone or can be accomplished remotely with a computer and modem via the RAA-E.

The following self check functions are supported:

1.System CPU initialize (Reset) History (Memory Block 5Bl) - The history (time and type) of resets (errors) generated in the system can be retrieved from the system programming mode. The last ten resets are stored. (Initial power up is always the first reset stored.1

500-3