Lexmark 637, CX510DE manual Troubleshooting 312, Step Problem is solved. Go to step

Troubleshooting			312
Action		Yes	No
Step 4		Go to step 5.	Securely connect the
Check the printer connections.			cables.
If applicable, check if the cable connections for the following
equipment are secure:
•	Telephone
•	Handset
•	Answering machine

Are the cable connections secure?

Step 5 The problem is solved. Go to step 6.

aCheck the telephone wall jack.

1Plug the telephone cable into the wall jack.

2Listen for a dial tone.

3If you do not hear a dial tone, then plug a different telephone cable into the wall jack.

4If you still do not hear a dial tone, then plug the telephone cable into a different wall jack.

5If you hear a dial tone, then connect the printer to that wall jack.

bTry sending or receiving a fax.

Can you send or receive a fax?
Step 6	Go to step 7.	Connect the printer to
Check if the printer is connected to an analog phone service or the correct		an analog phone
digital connector.		service or the correct
		digital connector.
The fax modem is an analog device. Certain devices can be connected
to the printer so that digital telephone services can be used.

•If you are using an ISDN telephone service, then connect the printer to an analog telephone port (an R-interface port) on an ISDN terminal adapter. For more information and to request an R- interface port, contact your ISDN provider.

•If you are using DSL, then connect to a DSL filter or router that will support analog use. For more information, contact your DSL provider.

•If you are using a PBX telephone service, then make sure you are connecting to an analog connection on the PBX. If none exists, then consider installing an analog telephone line for the fax machine.

Is the printer connected to an analog phone service or the correct digital connector?