Specifications

Maintenance and Trouble Shooting
72 Comdial October, ‘03
No system
operation.
CPU Heartbeat
LED Dark or
Lit steady
Memory strap
in “Cold Start”
position
If the memory strap is in the “Cold Start”
position, initialize the system as described in
Section 2.18, Power-up Initialization (Cold
Start).
Power Switch Switch the KSU AC power switch on the “ON”
position.
AC Fuse Switch KSU power to the OFF position and
remove cover (four screws). Locate the system
power supply in the upper left corner of the
KSU interior and inspect the AC fuse for
continuity (DVM required).
DC Fuse Switch KSU power to the OFF position and
remove cover (four screws). Locate the system
power supply in the upper left corner of the
KSU interior and inspect the AC fuse for
continuity (DVM required).
SPI Buss Error Switch KSU power to the OFF position and
remove cover (four screws). Then check for
the following:
1. Locate each expansion module and verify
the ribbon cable connection is accurate and
secure.
2. Check for improper aligning of module
connectors.
3. Detach all station cabling and retest.
4. Check all socketed IC's for good "seated"
connections.
5. Unplug one module at a time and retest until
failed component is found.
6. Perform Initialization and Power Up
sequence. Note: this is an emergency action
since the unique customer database will be
erased and the system will reboot with default
database programming.
7. If this does not clear the trouble, replace
KSU1 and initialize it as described in
Section
2.18, Power-up Initialization (Cold Start).
Symptom(s)
(Continued)
Diagnostic
Aid
Cause(s) Action