LTE RRC Failure Information r15

Message Fact Sheet

Protocol	lte-rrc	Network	lte
Spec	3GPP TS 36.331	Spec Section	5.6, 6.2.2
Direction	UE -> eNodeB	Message Type	Failure Reporting

Full message name	LTE RRC Failure Information r15
Protocol	LTE-RRC
Technology	LTE
Direction	UE -> eNodeB
Interface	Uu
Signaling bearer / channel	SRB1 / UL-DCCH
Typical trigger	Triggered when the UE has failure context to report under the release 15 FailureInformation branch.
Main purpose	Lets the UE deliver collected failure context so the network can investigate the event and continue with later recovery or optimization handling.
Main specification	3GPP TS 36.331, 5.6, 6.2.2
Release added	Release 15
Procedures where used	Failure information reporting

What is LTE RRC Failure Information r15 in simple terms?

Uplink LTE RRC message used by the UE to report release-specific failure information back to the network.

Lets the UE deliver collected failure context so the network can investigate the event and continue with later recovery or optimization handling.

Why this message matters

Failure Information r15 is the LTE UE report that gives the network extra failure context after a problem occurred.

Where this message appears in the call flow

Failure information reporting

LTE flow showing Failure Information r15 sent after earlier failure handling — Failure Information r15 appears after an earlier problem when the UE can return additional failure context to the network.

Call flow position: UE report sent when failure context needs to be uploaded to the network.

Typical state: The network is gathering failure-side evidence rather than executing a direct mobility command.

Preconditions:

The UE has failure information available to report.

Next likely message: Failure investigation or later reconfiguration

Failure log upload continuation

LTE flow showing Failure Information r15 used as post-failure evidence upload — The message is best read as a follow-on failure evidence report rather than as the original failure trigger.

Call flow position: UE report sent after recovery or reconnect so earlier failure context can still be examined.

Typical state: The report gives the network post-failure context that is not visible from only the current signaling branch.

Preconditions:

A relevant failure occurred earlier.
Connected-mode signaling is available again.

Next likely message: Investigation or optimization continuation

Call flow position

Previous message(s): Recovery or reconnect continuation

Next message(s): Failure investigation, Later connected-mode continuation

Message direction and transport

Sender and receiver: UE -> eNodeB

Interface: Uu

Domain: Access-side radio control and failure reporting

Signaling bearer: SRB1

Logical channel: UL-DCCH

Transport / encapsulation: Protected LTE RRC signaling in connected mode

Security context: Sent as protected connected-mode signaling.

Message Structure Overview

FailureInformation-r15 is an uplink failure-reporting message whose operational value is in the reported failure payload.

ASN.1 for LTE RRC Failure Information r15

FailureInformation-r15 ::= SEQUENCE {
  criticalExtensions CHOICE {
    c1 CHOICE {
      failureInformation-r15 FailureInformation-r15-IEs,
      spare3 NULL,
      spare2 NULL,
      spare1 NULL
    },
    criticalExtensionsFuture SEQUENCE {}
  }
}

How to read this ASN.1

Read it as a post-failure evidence message rather than a direct recovery command.

LTE RRC Failure Information r15 - Example Dump

UL-DCCH-Message
  message c1 : failureInformation-r15 : {
    criticalExtensions c1 : failureInformation-r15 : {
      failureInformation-r15 present
    }
  }

How to read this dump

The message is most useful when paired with the earlier failure branch it is describing.

Important Information Elements

IE	Required	Description
`failureInformation-r15`	Yes	Carries the release 15 failure information payload reported by the UE.

Detailed field explanation

`failureInformation-r15`

Carries the release 15 failure information payload reported by the UE.

Presence: Required

In practice: In practice, compare this field with the original request and with any later release-dependent optional fields so you can see whether the network accepted the same service model the UE asked for.

What to check in logs and traces

Identify the earlier failure event that likely triggered this report.
Check what branch or recovery path made the report possible.
Correlate the report with later investigation or reconfiguration.

Common Issues and Troubleshooting

A failure happened earlier, but the network-side trace does not explain it fully.

Likely cause: The UE may have returned Failure Information r15 to provide additional failure context.

What to inspect: Check the message timing relative to the earlier failure and later recovery path.

Next step: Read the report as supplementary failure evidence rather than a new failure event.

FAQ

What is Failure Information r15 in LTE?

It is the uplink LTE RRC message the UE uses to return release 15 failure information to the network.

Related message pages

Related Procedures

Related Tools

Use This Reference in Practice

Decode this message with the 3GPP Decoder, inspect the related message database, or open the matching call flow to see where this signaling step fits in the full procedure.