OFF mode and Alarm Mode on Q2501B



I meet some problems with the off mode and the alarm mode.
When I send the AT command by the hyper terminal I can see the module off and after the response +CALA but the consumption is 40mA instead of 9uA (during the off mode).

I use OS X55 with the demo board of the Q2501 module. For the Off mode the consumption is 40mA and in the fast idle mode the consumption is 20mA.

What is wrong ? My consumption is more in off mode than in fast idle ???

Thank for advance


i have only experiance on Q2406B. There it is neccessary to connect on/off pin to GND before submitting at+cpof or at+cfun=0.

Once started the Q2406 with on/off high, you can let this pin connected to GND. The module will perform at+cfun=1 ( complete reset) when your presetted alarm expieres.

hope it helps



I already test the off mode and the alarm mode with the 2406 and it works correctly.

On the 2501 I do the same test with GPS OFF (at+wgpsm=0,0 and at+wgpsant=0,0) but my consumption is more than fast idle mode!

I don’t understand because I see on the demo the only thing which increase my consumption is the serial port and the dc-dc converter uses to power GPS antenna but I disable the both.

If you have an idea !!!

Thanks for advance


Hi juls64,

please have a look on your Q2501 starterkit.
If the ON/~OFF pin is permanently connected with the power supply you have no possibility to switch off the modul completely.
If the ON/~Off pin is high and you send at+cpof or at+cfun=0 you will switch off only the gsm stack.
And this could be the reason why you have this high consumption.




When I test the consumption of the demo board without the 2501 I see 30mA. I think to test correctly the consumption I must do a custom card.

Thanks for your answers



don`t forget about Max chip, it takes power too!
on demo board you can turn it off by jumper.