Nortel Millennium multi-pay M1211, Инструкция по установке, эксплуатации и обслуживанию

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6-20 Troubleshooting strategies
Checking the CO line
If the terminal loses the telephone line voltage or dialtone
(error codes 21, 41 and 42), and the VFD works, trace the
line voltage and dial tone from their source, through the rear
terminal PCP, to the control PCP and the telephony PCP.
To prevent damage to the electrostatic-sensitive
devices inside the terminal, wear your ESD wrist
strap and connect it to the ESD connection points
shown in Figure 7-2.
Disconnect the power from the terminal. Do not
reconnect the power until you are ready to close the
terminal.
Failure to follow these procedures may damage the
electrostatic-sensitive devices.
1. Pull off the top terminal block from the rear terminal
PCP and snap it to the upper arm of the link assembly.
2. Probe the tip and ring (T and Ft) on the terminal block of
the rear terminal PCP. Look for approximately 48 V DC.
If voltage is not found at the terminal block, there is a
telephone line problem.
3. If voltage is present, listen for dialtone using a dial hand
test set. If dialtone is not heard, there is a telephone line
problem.
4. If dialtone is heard on the dial hand test set and the
problem continues, replace the handset. Refer to Re­
placing the handset and cord or the swivel in Chap­
te r? .
5. If this does not correct the problem, replace the rear ter­
minal PCP, and if necessary, the telephony PCP and
control PCP. Refer to Replacing the rear terminal
PCP and Replacing the control and telephony PCPs
in Chapter 7.
Figure 6-11 shows a flow chart demonstrating CO line
troubleshooting procedures.
Electrostatic
shock
(ESD)
precautions
NTP: 506-6501-203 Issue: 00.01 Status: Standard Date: January 1997