Avaya Definity SI Maintenance Manual page 115

Troubleshooting power units
8. If the yellow LED on the power supply does not light during the reseating of
the control circuit packs, unseat all port circuit packs.
9. Reseat the port circuit packs one at a time, as you did in Step 7 above.
10. Check for power to the tape drive unit and fans. These devices use
separate outputs from the power supply.
11. If none of the control or port circuit packs appears to be defective, check
the cabinet temperature.
12. If both the circuit packs and the ambient cabinet temperature can be
eliminated as potential trouble causes, replace the power unit (see
''Replacing power supplies and
13. Reboot the system.
14. When the system reboot has completed, return the EMER XFER
(Emergency Transfer) switch to AUTO (restores the system to the normal
operating mode).
Replacing power supplies and fans
General caution
Components can be replaced while the unit is attached to the wall. Also, if the
wires and cables at the back of the cabinet are neatly bundled, these wires and
cables need not be disconnected.
!
CAUTION:
When replacing either the power supply or the fans unit that is already
attached to the wall, you should disconnect the entire fan panel from the
unit. Otherwise, if the fan panel is left to dangle, the cable assemblies
leading from the fans (connected to the fan panel) and into the backplane
might become damaged or disconnected from the backplane.
Replacing the 1217A power supply
Use the following procedures below to replace the 1217A power supply, which
can replace any of these power units:
WP91153 L3
WP91153 L3A
WP91153 L4-25
WP91153 L4A-25
555-233-123
NOTE:
The 1217A power supply's thermal protection shuts it down if the
incoming air temperature is greater than 50
(3,049 m.) elevation or 60
°
C. (122
° °
C. (140 F.) at sea level.
fans'').
Issue 4 May 2002
° )
F. at 10,000 ft.
5-11