Section: 6.5.1.5 Abnormal cases in the UE
Content: The following abnormal cases can be identified: a) T3482 expired On the first expiry of the timer T3482: - if the PDN CONNECTIVITY REQUEST message was sent with request type set to "emergency" or "handover of emergency bearer services" in a stand-alone PDN connectivity procedure, then the UE shall: a) inform the upper layers of the failure to establish the emergency bearer; or NOTE: This can result in the upper layers requesting establishment of a CS emergency call (if not already attempted in the CS domain), or other implementation specific mechanisms, e.g. procedures specified in 3GPP TS 24.229[ IP multimedia call control protocol based on Session Initiation Protocol (SIP) and Session Description Protocol (SDP); Stage 3 ]  [13D] can result in the emergency call being attempted to another IP-CAN. b) detach locally, if not detached already, attempt EPS attach for emergency bearer services. - otherwise, the UE shall resend the PDN CONNECTIVITY REQUEST and shall reset and restart timer T3482. This retransmission is repeated four times, i.e. on the fifth expiry of timer T3482, the UE shall abort the procedure, release the PTI allocated for this invocation and enter the state PROCEDURE TRANSACTION INACTIVE. b) T3447 is running The UE shall not send a PDN CONNECTIVITY REQUEST message when the UE is in EMM-CONNECTED mode after the UE attached without PDN connection, unless: - establishment of a PDN connection for emergency bearer services is requested; - the UE is a UE configured to use AC11 – 15 in the selected PLMN; or - a network initiated signalling message has been received. The PDN CONNECTIVITY REQUEST message can be sent, if still necessary, when timer T3447 expires. c) Collision of UE requested PDN connectivity procedure and NAS signalling connection release The UE may immediately retransmit the PDN CONNECTIVITY REQUEST message and stop, reset and restart timer T3482, if the following conditions apply: 1) the original UE requested PDN connectivity procedure was initiated over an existing NAS signalling connection; and 2) the previous transmission of the PDN CONNECTIVITY REQUEST message was not initiated due to timer T3482 expiry.