Section: 5.5.1.3.6 Abnormal cases in the UE
Content: The UE shall proceed as follows: 1) if the UE requested the combined attach for EPS services and "SMS only" and the ATTACH ACCEPT message indicates a combined attach successful for EPS and non-EPS services, the UE shall behave as if the combined attach was successful for EPS services and "SMS only"; NOTE 1: In this case the UE can ignore the CS SERVICE NOTIFICATION message or the Paging with CN domain indicator set to "CS", as specified in clause 5.6.2.3.2. 2) if the combined attach was successful for EPS services only and the ATTACH ACCEPT message contained an EMM cause value not treated in clause 5.5.1.3.4.3 or the EMM cause IE is not included in the message, the UE shall proceed as follows: a) The UE shall stop timer T3410 if still running, and shall enter state MM IDLE. The tracking area updating attempt counter shall be incremented, unless it was already set to 5; b) If the tracking area updating attempt counter is less than 5: - the UE shall start timer T3411, shall set the EPS update status to EU1 UPDATED and shall enter state EMM-REGISTERED.ATTEMPTING-TO-UPDATE-MM. When timer T3411 expires the combined tracking area updating procedure indicating "combined TA/LA updating with IMSI attach" is triggered; c) If the tracking area updating attempt counter is equal to 5: - a UE operating in CS/PS mode 2 of operation and a UE operating in CS/PS mode 1 of operation with "IMS voice available" shall start timer T3402 if the value of the timer as indicated by the network is not zero, shall set the EPS update status to EU1 UPDATED and shall enter state EMM-REGISTERED.ATTEMPTING-TO-UPDATE-MM. - If the value of T3402 as indicated by the network is zero, the UE shall perform the actions defined for the expiry of the timer T3402. - When timer T3402 expires the combined tracking area updating procedure indicating "combined TA/LA updating with IMSI attach" is triggered; and - a UE operating in CS/PS mode 1 of operation with "IMS voice not available" shall attempt to select GERAN, UTRAN or NG-RAN radio access technology and proceed with appropriate MM, GMM or 5GMM specific procedures. If the UE selects GERAN or UTRAN radio access technology, the UE may disable the E-UTRA capability (see clause 4.5). If No E-UTRA Disabling In 5GS is enabled at the UE (see 3GPP TS 24.368[ Non-Access Stratum (NAS) configuration Management Object (MO) ]  [50] or 3GPP TS 31.102[ Characteristics of the Universal Subscriber Identity Module (USIM) application ]  [17]) and the UE selects NG-RAN radio access technology, it shall not disable the E-UTRA capability; otherwise, the UE may disable the E-UTRA capability as specified in clause 4.5; and NOTE 2: Whether the UE requests RRC to treat the active E-UTRA cell as barred (see 3GPP TS 36.304[ Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) procedures in idle mode ]  [21]) is left to the UE implementation. d) If there is a CS fallback emergency call pending or CS fallback call pending, the UE shall attempt to select GERAN or UTRAN radio access technology. If the UE finds a suitable GERAN or UTRAN cell, it then proceeds with the appropriate MM and CC specific procedures; otherwise the EMM sublayer shall indicate the abort of the EMM procedure to the MM sublayer; and 3) otherwise, the abnormal cases specified in clause 5.5.1.2.6 apply with the following modification. If the attach attempt counter is incremented according to clause 5.5.1.2.6 the next actions depend on the value of the attach attempt counter: - if the attach attempt counter is less than 5, the UE shall set the update status to U2 NOT UPDATED but shall not delete any LAI, TMSI, ciphering key sequence number and list of equivalent PLMNs; or - if the attach attempt counter is equal to 5, then the UE shall delete any LAI, TMSI, ciphering key sequence number and list of equivalent PLMNs and set the update status to U2 NOT UPDATED. - The UE shall attempt to select GERAN, UTRAN or NG-RAN radio access technology and proceed with appropriate MM, GMM or 5GMM specific procedures. Additionally, if the UE selects GERAN or UTRAN radio access technology, the UE may disable the E-UTRA capability as specified in clause 4.5. If No E-UTRA Disabling In 5GS is enabled at the UE (see 3GPP TS 24.368[ Non-Access Stratum (NAS) configuration Management Object (MO) ]  [50] or 3GPP TS 31.102[ Characteristics of the Universal Subscriber Identity Module (USIM) application ]  [17]) and the UE selects NG-RAN radio access technology, it shall not disable the E-UTRA capability; otherwise, the UE may disable the E-UTRA capability as specified in clause 4.5. NOTE 3: Whether the UE requests RRC to treat the active E-UTRA cell as barred (see 3GPP TS 36.304[ Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) procedures in idle mode ]  [21]) is left to the UE implementation. If there is a CS fallback emergency call pending or CS fallback call pending, the UE shall attempt to select GERAN or UTRAN radio access technology. If the UE finds a suitable GERAN or UTRAN cell, it then proceeds with the appropriate MM and CC specific procedures; otherwise the EMM sublayer shall indicate the abort of the EMM procedure to the MM sublayer.