> 19.6.1 | ME status indicated by status LED patterns

> The following table lists the possible patterns of status LED behavior, and describes the ME operating status indicated by each pattern if AT^SSYNC parameter <mode>=1 and <mode>=2. To better monitor the operating states while power saving is enabled, we recommend that priority be given to <mode>=2.
> During the transition from one LED pattern to another the "on" and/or "off" periods of the LED may vary in length. This is because an event that triggers the change may occur any time and, thus, truncate the current LED pattern at any point.
> The statements on LED behavior during SLEEP mode are not applicable if the USB cable is plugged. This is because power saving with connected USB host does not take effect if set with AT+CFUN only. For details see notes provided with AT+CFUN. Therefore, while the USB cable is plugged, the LED is always on and flashes as if the module works at AT+CFUN=1, no matter whether AT^SSYNC=1 or AT^SSYNC=2 is enabled.

> Table 19.1: | Modes of the LED and indicated ME functions

> LED behavior | ME operating status if AT^SSYNC=1 | ME operating status if AT^SSYNC=2
> Permanently off | ME is in one of the following modes: - POWER DOWN mode - AIRPLANE mode - CHARGE ONLY mode - NON-CYCLIC SLEEP mode - CYCLIC SLEEP mode with no temporary wake-up event in progress 1) | ME is in one of the following modes: - POWER DOWN mode - AIRPLANE mode - CHARGE ONLY mode
> 600 ms on / 600ms off | Limited Network Service: No SIM card inserted or no PIN entered, or network search in progress, or ongoing user authentication, or network login in progress. | Same as for AT^SSYNC=1
> 75 ms on / 3 s off | IDLE mode: The mobile is registered to the GSM network (monitoring control channels and user interactions). No call is in progress. | Same as for AT^SSYNC=1
> 75 ms on / 75 ms off / 75 ms on / 3 s off | One or more GPRS PDP contexts activated. | Same as for AT^SSYNC=1
> 500 ms on / 50 ms off | Packet switched data transfer is in progress. | Same as for AT^SSYNC=1
> Permanently on | Depending on type of call: Voice call: Connected to remote party. Data call: Connected to remote party or exchange of parameters while setting up or disconnecting a call. | Same as for AT^SSYNC=1
> <n> ms on / <n> ms off 2) | Not possible: With AT^SSYNC=1, LED signalization is disabled in SLEEP mode. | SLEEP mode is activated (AT+CFUN parameter <fun> ≠ 1), but the ME is not registered to the GSM network (e.g. SIM not inserted or PIN not entered, and therefore, either no network service or only Limited Network Service is available.
> 25 ms on / 4 * <n> ms off 2) | Not possible: With AT^SSYNC=1, LED signalization is disabled in SLEEP mode. | SLEEP mode is activated (AT+CFUN parameter <fun> ≠ 1) while the ME is registered to the GSM network and in IDLE mode.
> 25 ms on / <m> ms off / 25 ms on / 3 * <m> ms off 2) | Not possible: With AT^SSYNC=1, LED signalization is disabled in SLEEP mode. | SLEEP mode is activated (AT+CFUN parameter <fun> ≠ 1) while the ME is registered to the GSM network. Additionally, PDP context is activated.

> 1) When a temporary wake-up event (for example a call, a URC, a packet switched transfer) occurs in CYCLIC SLEEP mode the LED flashes according to the patterns listed above. See Section 2.9.1, Wake up the ME from SLEEP mode for details on the various SLEEP modes and wake-up events.
> 2) The duration of <n> and <m> depends on the network: In SLEEP mode, the module can only change its LED status during intermittent wake-up periods when listening to paging information from the base station. Therefore the values of <n> and <m> vary as follows:
> <n> = value from 471 ms to 2118 ms
> <m> = 3000 ms