Troubleshooting guide

Is the cable pinout correct?
If the ATM0 interface status is down and down, the router is not seeing a carrier on the ADSL line. This
generally indicates one of two issues:
The active pins on the DSL wall jack are incorrect.1.
Your ISP has not turned up a DSL service on this wall jack.2.
Cisco DSL Router xDSL Port Pinouts
The RJ−11 connector provides an xDSL connection to external media via a standard RJ−11 6−pin modular
jack.
Pin Description
3 XDSL_Tip
4 XDSL_Ring
To determine if the ATM0 interface is down and down, issue the show interface atm 0 command from
enable mode of the router.
Router#show interface atm 0
ATM0 is down, line protocol is down
<... snipped ...>
If the ATM interface is down and down—not administratively down—check the pinout of your DSL wall
jack. The DSL Router uses a standard RJ−11 (4−pin or 6−pin) cable to provide the ADSL connection to the
wall jack. The center pair of pins on the RJ−11 cable is used to carry the ADSL signal (pins 3 and 4 on a
6−pin cable, or pins 2 and 3 on a 4− pin cable).
If you are sure you have the right pins on the wall jack and the ATM0 interface is still down and down,
replace the RJ−11 cable between the DSL port and your wall jack. If the interface is still down and down after
replacing the RJ−11 cable, contact your ISP and have the ISP verify that DSL service has been enabled on the
wall jack you are using.
If you are not sure what pins on your wall jack are active, ask your ISP.
Do you have the correct power supply for the Cisco 827?
If you have verified that your ADSL cable is good and that you have the correct pinouts, the next step is to
make sure you have the correct power supply for the 827.
Note: The 827 does not use the same power supply as other 800 series routers.
To determine if you have the correct power supply, on the back of the power adapter look for Output +12V
0.1A, −12V 0.1A, +5V 3A, −24V 0.12A, and −71V 0.12A. If your power supply is missing the +12V and
−12V feeds, then it is for a different Cisco 800 series router and will not work on the 827. Note that if you use
the wrong power supply, the Cisco 827 will power up but will be unable to train up (connect) to the ISP
DSLAM.
Cisco DSL Router Configuration and Troubleshooting Guide