Troubleshooting
Phone Rings-Back Upon Hanging Up
Step 1. User may have hook-flashed phone sometime during use and still had a trunk on soft hold
upon hanging-up.
Step 2. If more than four beeps are heard when lifting receiver, an unanswered transfer call is
returning because the allowed timeout has expired.
System Misdials or Won’t Allow Access (Intermittent)
Step 1. There are 2 receivers in the TCIV each one decodes the tones and sends them to the CPU for
processing. If one receiver improperly decodes a digit a problem will occur only when that
receiver is used. The first phone to pick up always gets the first receiver. Use the diagnostics
in the laptop computer to check the receivers. If one is defective, replace the MIO.
Alternate
Method: Temporarily turn off the Receiver Time Limit (Location Code 64012).
Leave a phone off hook to tie up one receiver and verify the remaining receiver operates by
picking up and using each key in turn to break the dial tone.
Interim
solution: Lock out a receiver with software until repairs can be ma&.
Talk Path Noisy or Dead (Intermittent)
Step 1. Use #75 diagnostic and test all 16 links in system, using a touch key to send a tone. Defects
with particular links can be further categorized as follows:
Defect on one line only: Suspect U2 or U3 on the affected LLM line.
Defect on
all lines of 1 LLM:
Suspect U7 or Connector 2 on the affected LLM.
Defect on multiple LLM’s:
Try another source phone and check the LLM cable
from the MIO.
Step 2. Perform the
Loop Check Procedure
or tty replacing the LLM line hybrid
Ul .
Crosstalk On Lines
Step 1. Check wiring and ensure it is correct. All phone wiring must consist of twisted pairs to LLM
T
and R terminals.
Step
2.
If line amps are in use, verily the negative of the power supply is connected to TCIV common
as shown in Drawing KM0716.
Step 3. If repeater amps arc installed, verify the 28vdc power supply is grounded (negative side to
MI0
pin Z on the B strip).
Step
4. Go
to the
Supplementary Procedures
and perform the Line
Rebalancing Procedure
to im-
prove the balance of TCIV lines from the typical 10% to 30% unbalance to 2% or less if the
crosstalk is associated with key phones and cables.
Note:
Balance is most important where long multi-pair cables are used, such as with key systems.
Page
18 of 30 1989 Rauland-Borg Corporation (Orig. 10/88; Rev. l/89)
