Chapter 3 - Troubleshooting

Situation C: The modem always returns «No carrier» when trying to issue a communication

Solutions for “no carrier” message

If the modem

 

Then ask …

 

Action

returns …

 

 

 

 

no carrier(esp. for

 

Is the selected

 

Type AT+CEER to view the extended error code

data communi-

 

bearer type

 

(see “Extended Error Report (+CEER) in the AT

cation)

 

supported by the

 

Command guide).

 

 

called party?

 

Be sure that the selected bearer type is supported

 

 

 

 

 

 

Is the selected

 

by the called party.

 

 

bearer type

 

Be sure that the selected bearer type is supported

 

 

supported by the

 

 

 

 

by the network.

 

 

network?

 

 

 

 

 

 

 

 

 

If no success, try bearer selection type:

 

 

 

 

AT+CBST=0,0,3

 

 

 

 

If the modem

 

Then ask …

Action

returns

 

 

 

 

 

 

 

 

 

no carrier

 

 

 

Be sure that the semicolon character (“;”) is typed

(esp. for voice

 

 

immediately after the phone number in the AT

communi-cation)

 

 

command; e.g., ATD######;

 

 

 

 

type AT+CBST=0,0,3

 

 

 

 

 

 

 

Is the received

 

See “Signal Strength Verification”.

 

 

signal strong

 

 

 

 

enough?

 

 

 

 

Is the antenna

 

See “Antenna/RF Specifications”.

 

 

properly

 

 

 

 

connected?

 

 

Multi-Tech Systems, Inc. MultiModem CDMA User Guide

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