Toshiba DK 16, DK8 manual Chart no CO Line Dial Tone Faults, Start

FAULT FINDING

SECTION 100-816-500

MARCH 1993

CHART NO. 4

CO LINE DIAL TONE FAULTS

START

1.Check CO line wiring per section 100-816-008.

2.Test central office line using a standard telephone or butt set at the

TELCO block.

Repair as necessary.

4-1

Is the fault	YES
cleared?
NO	YES
	4-3
4-2

Are all

faulty CO lines

on a replaceable PCB

(not including KSU

Main PCB )?

NO

NO 4-7

Are the

faulty CO lines	YES
		4-9
only in the DK16
expansion
unit?

END

Change the PCB and retest.

4-4

Is the

fault

cleared?

YES

4-5

Replace the defective unit and return it to the repair center.

END

Change the expansion

unit and retest.

Replaceable CO Line

PCBs

DK8: QCDU

DK16 Base: KCOU

DK16 Expansion:

KCDU, PCOU

NO

4-10

Change the DK8 or DK16 Base KSU and initialize the system (Prog: 90, 92, 03).

Retest.

4-6

Is the

fault

cleared?

NOTE:

Program 03 is not used on DK8.

YES

Go to

4-5

Is the

faultNO cleared?

YES

Go to

4-5

Call your technical

support group.

-10-