Dell 3115cn Service Manual page 38

PSTN
Manually dial any local phone
number (e.g. time service) using
touch tone.
C
Version 1 2006.11.21
PBX
The standard cable used for the
conventional analog telephone line
is RJ-11, which has two conductors.
However, the four-conductor cables
commonly available are backward
compatible with RJ-11 and can be
used with no problem. On the other
hand, since these four-conductor
cables are also used for ISDN
systems, the number of elements is
not the key for identification of the
type of line/service.
- A continuous tone is present at
Yes
- The cable has two conductors.
Yes
Connection
established?
Check for the pulse.
Manually dial using pulse
20PPM.
C
Yes
A
Check the line type
PSTN?
off hook.
Yes
D
No
No
Connection
established?
Set to pulse 10PPM.
Chapter 1 Troubleshooting
- Confirm that the line is not an
ISDN/xDSL/IP phone line but
an analog telephone line.
- If no dial tone is present at off
hook, the line may be faulty.
No
Is an intermittent
tone present at
off hook?
No
PBX?
Request the telephone
company for a line
repair.
C