8.1 Troubleshooting

For the most frequently asked questions refer to faq.2n.cz.

  • No LED is shining on 2N® BRI Enterprise / BRI Lite.
    • 2N® BRI Enterprise / BRI Lite is disconnected from the power supply.
  • 2N® BRI Enterprise / BRI Lite fails to log in to the GSM network.
    • Check the SIM card.
    • Check the PIN.
    • Check the antenna connection.
    • Select a place with a good GSM signal.
  • When I make outgoing call thru the GW, the call is rejected by the gateway. What may cause it?
    • The communication protocol on the line from your PbX to the gateway is set to Euro ISDN DSS1 according to Q.931
    • The SIM cards are logged to the network correctly – both LEDs called GSM1 and GSM2 must be off (they are blinking during logging process, but they go off after they are logged successfully)
    • You see good signal strength in the Diagnostics (between −60dB and −80 dB)
    • The SIM cards are active, they have credit, they are not blocked by the GSM operator
    • If you are using CLIR function Enabled in the gateway, check if this feature is enabled in the SIM card by the GSM operator
    • The dialed number is in correct format, it matches one of the Network Lists and this Network List is Actively used in the LCR section
    • If you have set Max. number of called minutes, make sure those minutes have not been already used up.
    • The Time limitation of SIM card (which part of the day it shall be used) is set correctly
    • Time and Date is set correctly in the Gateway
  • Call is not disconnected immediately
    • Call release in GSM network can take up to 2 s. If you are experimenting longer delay it can be caused by gateway or by PBX settings. Usually the connection stays active because of simulation of analogue line. If call is disconnected in analogue line you can hear busy tone. This is not typical anymore in ISDN networks but you can simulate this behaviour and generate busy tone up to 30 s.
    • On gateway side you can set following:

If call stays up when call is disconnected from GSM side. Go to ISDN parameters and set Busy tone on None. (This is turning off busy tone generation from gateway.)

If call stays up when call is disconnected from PBX side. Go to GSM Basic parameters and set Busy tone on None. (This is turning off busy tone generation from gateway). If call is not cut after this settings set this parameter on Disabled. (If PBX requests to keep line active in disconnection message then gateway will ignore this request and the call will be ended)