UE camping to overshoot cell in 3G after Extended Service Msg

Hi Experts.
It is observed that after Extended Service Msg UE camp to overshoot cell in 3G, without flow the Normal procedure of RRC Connection request in LTE.
It directly camp to the overshoot cell with no call establishment on this.
What could be the reason of this?
No issue found in legacy layer.


Is it CSFB?

Yes, CSFB.

eNB send UE UTRAN frequency, UE self search and camp on any detected Ucell.

But after extended Service MSG, we could not see any MSG related to UTRAN frequency.

It should be in the RRC connection release.

As per knowlege after extended service MSG, RRC Request and Complete MSG will come then Security MSGs.

Can you check if any layer 3 messages skipped?

No, Extended service request is NAS message, mean that RRC connection is already established before.
Now, in RRC conn release, eNB will send UE with UTRAN frequency.

I have checked already.


OK, this is normal procedure after Extended Service Request, UE send RRC Connection request MSG, then setup and setup complete.

Not normal.

There is 400 ms gap when going from time .52 to .53
Rest all messages are less time.
Signalling is missing.

Let me check again.

What is RRC establishment cause in RRC conn request?

Let me check. But after camping on this cell multiple RRC connection request sent, but no reply from eNB, then routing update and camp to the desired cell.

Not able to see between signaling tried.

It’s because that approx 400ms signalling is missed and main 2 3 steps were missed in it.
You can do re drive on same patch.

Redrive have done and no issue observed. But i want to find the reason in pre.

It’s a tool bug you can see, we have seen this thing in TEMs and NEMO specially, plus another factor is that handset temperature also matters, when it heated up too much it mostly hang, skip signalling or loss in signal.

In post drive you didn’t saw any signalling missed issue, right?

Yup… smooth.