Sim900 does not initialize


#1

In my sim900 board when torn on the power key button the led status torn on. When torn off power key button the led status torn off. The led netnight, it is always off. The power of board is external with 5vcc and 2.5A supply power. Before, the board ware working normally. Please, what is this problem?
It is link for video https://youtu.be/AW4m4AZxQ-o


#2

Hi ,
What you mean by turn on PWRKEY button.?
PWRKEY pin should be pulled low for a second to turn the module ON. Then you should release it.
Regards,
Ravi


#3

Torn on power key button is to press button or close the circuit.


#4

Hi Ravi, I did put a link in the post. In this video, I show how is problem.
Thank you.


#5

Where is the NETLIGHT LED on board? Is RED LED indicating power supply?

Are you trying to ground the PWRKEY line using the probe?
You should GROUND and leave it for a few seconds for NETLIGHT to turn on. What is voltage measured on VBAT pins of module?


#6

The pin netlight is always off. The led red on is power supply. I used the probe to close the circuit pwrkey, to ground the pwrkey. I ground this pin by many seconds. The voltage measured in vbat pin is 4.16V.


#7

This is strange, May be your module is dead or you are not grounding the PWRKEY pin. Recheck if the pin you are grounding is the PWRKEY pin only.

Try grounding on the GSM pin itself rather than on the connector to be sure.


#8

Yes, I tried to connect pin one directily to ground.


#9

May be you should try one more new module to save time.