1 Normal class
1.1 Cause No. 1 "unassigned (unallocated) number"（未分配的号码）
This cause indicates that the destination requested by the mobile station cannot be reached because, although the number is in a valid format, it is not currently assigned (allocated).
1.2 Cause No. 3 "no route to destination"（目的地无路由）
This cause indicates that the called user cannot be reached because the network through which the call has been routed does not serve the destination desired.
1.3 Cause No. 6 "channel unacceptable"（信道无法接受）
This cause indicates the channel most recently identified is not acceptable to the sending entity for use in this call.
1.4 Cause No. 8 "operator determined barring"（操作者定义禁止）
This cause indicates that the MS has tried to access a service that the MS's network operator or service provider is not prepared to allow.
1.5 Cause No.16 "normal call clearing"（正常的呼叫清除）
This cause indicates that the call is being cleared because one of the users involved in the call has requested that the call be cleared.
Under normal situations, the source of this cause is not the network.
1.6 Cause No.17 "user busy"（用户忙）
This cause is used when the called user has indicated the inability to accept another call.
It is noted that the user equipment is compatible with the call.
1.7 Cause No. 18 "no user responding"（用户无响应）
This cause is used when a user does not respond to a call establishment message with either an alerting or connect indication within the prescribed period of time allocated (defined by the expiry of either timer T303 or T310).
1.8 Cause No. 19 "user alerting, no answer"（用户振铃，无应答）
This cause is used when a user has provided an alerting indication but has not provided a connect indication within a prescribed period of time.
1.9 Cause No. 21 "call rejected"（呼叫拒绝）
This cause indicates that the equipment sending this cause does not wish to accept this call, although it could have accepted the call because the equipment sending this cause is neither busy nor incompatible.
1.10 Cause No. 22 "number changed"（号码变换）
This cause is returned to a calling mobile station when the called party number indicated by the calling mobile station is no longer assigned. The new called party number may optionally be included in the diagnostic field. If a network does not support this capability, cause No. 1 "unassigned (unallocated) number" shall be used.
1.11 Cause No. 26 "non-selected user clearing"（未选择的用户清除）
Not supported. Treated as cause no. 31.
1.12 Cause No. 27 "destination out of order"（目的端命令超出）
This cause indicates that the destination indicated by the mobile station cannot be reached because the interface to the destination is not functioning correctly. The term "not functioning correctly" indicates that a signalling message was unable to be delivered to the remote user; e.g., a physical layer or data link layer failure at the remote user, user equipment off-line, etc.
1.13 Cause No. 28 "invalid number format (incomplete number)"（非法的号码格式（不完整的号码）
This cause indicates that the called user cannot be reached because the called party number is not a valid format or is not complete.
1.14 Cause No. 29 "facility rejected"（设备拒绝）
This cause is returned when a facility requested by user can not be provided by the network.
1.15 Cause No. 30 "response to STATUS ENQUIRY"（响应STATUS ENQUIRY）
This cause is included in STATUS messages if the message is sent in response to a STATUS ENQUIRY message. See also section 5.5.3.
1.16 Cause No. 31 "normal, unspecified"（一般，未定义）
This cause is used to report a normal event only when no other cause in the normal class applies.
2 Resource unavailable class
2.1 Cause No. 34 "no circuit/channel available"（无电路/信道可用）
This cause indicates that there is no appropriate circuit/channel presently available to handle the call.
2.2 Cause No. 38 "network out of order"（网络命令超出）
This cause indicates that the network is not functioning correctly and that the condition is likely to last a relatively long period of time; e.g., immediately re-attempting the call is not likely to be successful.
2.3 Cause No. 41 "temporary failure"（临时失败）
This cause indicates that the network is not functioning correctly and that the condition is not likely to last a long period of time; e.g., the mobile station may wish to try another call attempt almost immediately.
2.4 Cause No. 42 "switching equipment congestion"（交换设备拥塞）
This cause indicates that the switching equipment generating this cause is experiencing a period of high traffic.
2.5 Cause No. 43 "access information discarded"（接入信息丢弃）
This cause indicates that the network could not deliver access information to the remote user as requested; i.e., a user-to-user information, low layer compatibility, high layer compatibility, or sub-address as indicated in the diagnostic.
It is noted that the particular type of access information discarded is optionally included in the diagnostic.
2.6 Cause No. 44 "requested circuit/channel not available"（请求的电路/信道不可用）
This cause is returned when the circuit or channel indicated by the requesting entity cannot be provided by the other side of the interface.
2.7 Cause No. 47 "resource unavailable, unspecified"（资源不可用，未定义）
This cause is used to report a resource unavailable event only when no other cause in the resource unavailable class applies.
3 Service or option not available class
3.1 Cause No. 49 "quality of service unavailable"（业务质量（QOS）不可用）
This cause indicates to the mobile station that the requested quality of service, as defined in CCITT Recommendation X.213, cannot be provided.
3.2 Cause No. 50 "Requested facility not subscribed"（请求的设备未预定）
This cause indicates that the requested supplementary service could not be provided by the network because the user has no completed the necessary administrative arrangements with its supporting networks.
3.3 Cause No. 55 "Incoming calls barred within the CUG"（在ＣＵＧ中来话禁止）
This cause indicates that although the called party is a member of the CUG for the incoming CUG call, incoming calls are not allowed within this CUG.
3.4 Cause No. 57 "bearer capability not authorized"（承载能力未授权）
This cause indicates that the mobile station has requested a bearer capability which is implemented by the equipment which generated this cause but the mobile station is not authorized to use.
3.5 Cause No. 58 "bearer capability not presently available"（承载能力当前不可用）
This cause indicates that the mobile station has requested a bearer capability which is implemented by the equipment which generated this cause but which is not available at this time.
3.6 Cause No. 63 "service or option not available, unspecified"（业务或选件不可用，未定义）
This cause is used to report a service or option not available event only when no other cause in the service or option not available class applies.
3.7 Cause No. 68 "ACM equal to or greater than ACMmax"（ＡＣＭ大于等于ＡＣＭ最大值）
This cause is used by the mobile to indicate that call clearing is due to ACM （累计呼叫次数）being greater than or equal to ACMmax.
4 Service or option not implemented class
4.1 Cause No. 65 "bearer service not implemented"（承载业务无法实现）
This cause indicates that the equipment sending this cause does not support the bearer capability requested.
4.2 Cause No. 69 "Requested facility not implemented"（请求的设备不可执行）
This cause indicates that the equipment sending this cause does not support the requested supplementary service.
4.3 Cause No. 70 "only restricted digital information bearer capability is available"（有限的数字承载能力可用）
This cause indicates that one equipment has requested an unrestricted bearer service, but that the equipment sending this cause only supports the restricted version of the requested bearer capability.
4.4 Cause No. 79 "service or option not implemented, unspecified"（业务或选项不可执行，未定义）
This cause is used to report a service or option not implemented event only when no other cause in the service or option not implemented class applies.
5 Invalid message (e.g., parameter out of range) class
5.1 Cause No. 81 "invalid transaction identifier value"（无效的传送标识符）
This cause indicates that the equipment sending this cause has received a message with a transaction identifier which is not currently in use on the MS-network interface.
5.2 Cause No. 87 "user not member of CUG"（用户非ＣＵＧ成员）
This cause indicates that the called user for the incoming CUG call is not a member of the specified CUG.
5.3 Cause No. 88 "incompatible destination"（矛盾的目的地）
This cause indicates that the equipment sending this cause has received a request to establish a call which has low layer compatibility, high layer compatibility, or other compatibility attributes (e.g., data rate) which cannot be accommodated.
5.4 Cause No. 91 "invalid transit network selection"（无效的传输网络选择）
For further study. Treated as cause no. 95.
5.5 Cause No. 95 "semantically incorrect message"（语义错误消息）
This cause is used to report receipt of a message with semantically incorrect contents (see section 8.8).
6 Protocol error (e.g., unknown message) class
6.1 Cause No. 96 "invalid mandatory information"（无效的强制消息）
This cause indicates that the equipment sending this cause has received a message with a non-semantical mandatory IE error (see section 8.5).
6.2 Cause No. 97 "message type non-existent or not implemented"（消息类型不存在或不可实现）
This cause indicates that the equipment sending this cause has received a message with a message type it does not recognize either because this is a message not defined, or defined but not implemented by the equipment sending this cause.
6.3 Cause No. 98 "message type not compatible with protocol state"（消息类型与协议状态不一致）
This cause indicates that the equipment sending this cause has received a message not compatible with the protocol state (section 8.4).
6.4 Cause No. 99 "information element non-existent or not implemented"（消息元素不存在或不可执行）
This cause indicates that the equipment sending this cause has received a message which includes information elements not recognized because the information element identifier is not defined or it is defined but not implemented by the equipment sending the cause. However, the information element is not required to be present in the message in order for the equipment sending the cause to process the message.
6.5 Cause No. 100 "conditional IE error"（有条件的IE错）
This cause indicates that the equipment sending this cause has received a message with conditional IE errors (see section 8.7.2).
6.6 Cause No. 101 "message not compatible with protocol state"（消息与协议状态不兼容）
This cause indicates that a message has been received which is incompatible with the protocol state or that a STATUS message has been received indicating an incompatible call state.
6.7 Cause No. 102 "recovery on timer expiry"（定时器超时恢复）
This cause indicates that a procedure has been initiated by the expiry of a timer in association with TS 04.08 error handling procedures.
6.8 Cause No. 111 "protocol error, unspecified"（协议错误，未定义）
This cause is used to report a protocol error event only when no other cause in the protocol error class applies.
7 Interworking class
7.1 Cause No. 127 "interworking, unspecified"（互联，未定义）
This cause indicates that there has been interworking with a network which does not provide causes for actions it takes; thus, the precise cause for a message which is being sent cannot be ascertained.