61202.070L1-1 Express L128/L128T User Manual 107
Chapter 4
Troubleshooting
When the Express L128/L128T powers up, it performs an internal self-test.
This takes about 10 seconds. At the end of the test, the PWR LED should flash.
IF SELF-TEST FAILS
If the PWR LED is not on or continuously flashes, the following steps will ver-
ify whether or not the problem can be fixed locally.
1. Ensure the Express L128/L128T is receiving power.
2. Power off the Express L128/L128T. Place switch 2 in the off position; then
power back up. This will reset all internal settings to their factory default.
3. If the Express L128/L128T still does not pass self-test, call ADTRAN Tech-
nical Support for assistance. See the inside back cover of this manual for
information on contacting ADTRAN.
IF THE EXPRESS L128/L128T DOES NOT READ
READY
When the Express L128/L128T has been set up and connected to a line, but the
PWR LED does not remain on after a few minutes, proceed with the following
steps:
1. Cycle power on the Express L128/L128T, leaving it off for a minimum of
two seconds; then turn the power on for one minute to ensure the PWR
LED still doesn’t stay on.
2. Disconnect the Express L128/L128T. From a functioning voice phone, call
the local directory number(s) provided with your line. Calling a good
ISDN line with nothing connected usually results in a ring or fast busy
tone. If someone answers, or you get a not-in-service intercept, there is
