Can't send messages and make calls

I work with SL6087 module and there are problems that I can’t solve. My distributor has not helped me yet, so I hope you’ll help me. The GSM network and the SIM card are detected successfully and the level of a signal is hight, but I can’t send SMS and make calls (but it works with another device - Q24PL).

If SIM card is not inserted, the module returns

+WIND: 3

+WIND: 0

+WIND: 7

and AT+CSQ returns a value about 18-20

+CSQ: 20,0

But when SIM card is inserted I get strange result - sometimes the network is lost and after 30 minutes I have following result

+WIND: 8

+WIND: 7

+WIND: 8

+WIND: 7

(so there are moments when the network is available (5-10 minutes) and moments when network is lost (1-5 minutes) )

and AT+CSQ returns variable results

AT+CSQ
+CSQ: 99,99
OK

AT+CSQ
+CSQ: 25,99
OK

AT+CSQ
+CSQ: 99,99
OK

AT+CSQ
+CSQ: 14,99
OK

AT+CSQ
+CSQ: 14,0
OK

And results of ATD and AT+CGMS commands are as follow

ATD89031577934;
+WIND: 5,1
OK
+WIND: 6,1

AT+CMGS=“89031577934”

Test…
ERROR

(it also works so with my country code +7 and I have tried all possible variants of syntax of these commands)

The problem was solved. It was a problem of VBATT line. My VBATT line was too narrow and the module couldn’t turn a transfer procedure on.

FAQ!

https://forum.sierrawireless.com/t/faq-forum-wiki/3491/1