AT&T MERLIN LEGEND Release 3.0 Installation Manual page 386

Power Supply Problems
Replacing Auxiliary Power Units
Follow this procedure if any of the following symptoms occur:
The LEDs on the multiline telephones that are connected to the last
two modules in the carrier do not light.
The last two slots in the carrier do not have power.
The power supply LED is off.
To replace the auxiliary power unit, follow the steps below. Refer to Figure 4-3
throughout this procedure.
1 Make sure the switch on the power supply module is turned off.
2 Unplug the power supply and the auxiliary power unit from the AC outlet.
3 Disconnect the cord from the AUX POWER INPUT jack on the power
supply module.
4 Remove the auxiliary power unit (with the two cords still attached).
5 Mount the replacement auxiliary power unit in place of the old one.
6 Plug the power unit line cord into the J2 DC OUTPUT jack on the
replacement auxiliary power unit.
7 Plug the other end of the power unit line cord into the AUX POWER
INPUT jack on the power supply.
4-8 Control Unit Problems