2(5)
Datum -
Date
Rev
Nr -
No.
Uppgjord
(även faktaansvarig om annan)
-
Prepared
(also subject responsible if other)
Dokansv/Godkänd -
Doc respons/Approved
Kontr -
Checked
File
1996-10-31
A
1541-DBC 211 01 Uen
MAINTENANCE INSTRUCTIONS
1
General
This document is to be used by service personnel when maintaining digital telephones
DBC 211 01, DBC 212 01 and DBC 213 01 with key panel DBY 409 01, designed for use with
defined releases of Ericsson's digital exchanges ASB 501 and ASB 150 02 or equivalent.
For spare parts, see 154 11-DBC 202+ Uen
2
Selftests
There are two types of selftest:
(1) automatic testing when the telephone is connected to a local power supply (48 V) or to an
exchange.
(2) testing initiated by the user pressing a special key combination.
The latter test can also be carried out with the telephone connected to the exchange or to a local
power supply. The testing refers primarily to the DBC 211 01, DBC 212 01 and DBC 213 01
telephones, whereas the test items applicable to DBY 409 01 are specially indicated in the text.
DBY 409 01 can only be tested together with the DBC 203 or DBC 213 telephone.
2.1
Automatic selftest (when connecting the telephone to ASB 501)
The automatic selftest is always carried out when connecting the telephone and comprises the
following functions/units: watchdog, RAM, D-channel, registers in the line communication circuit
(DASL), registers in the speech transmission circuit (COMBO) and the display.
If no fault is detected, the LED in the INQUIRY key is lit, and for DBC 212 and DBC 213 the
message "SELFTEST OK" is shown on the display for one second.
If a fault is detected, this is reported to the exchange when the telephone is activated, but no fault
indication is given on the telephone.
If no fault is detected in DBY 409 01, the bottom LED is lit for 1 second. If a fault is detected, no
LED is lit.
None of the units (DBC 211 01,DBC 212 01, DBC 213 01 and DBY 409 01)
should be repaired, except for replacement of parts listed in the spare parts list
Instead, the purpose of this instruction is to decide whether
the faults are located in the telephone set, in the exchange or line network.
