Motorola g20 Developer's Manual page 194

AT Commands Reference
AT+CLCK="SC",1
+CME ERROR: "operation not allowed"
(The SIM PIN is needed)
AT+CLCK="SC",1,"incorrect password +CME ERROR: INCORRECT_PASSWORD
AT+CLCK="SC",1,"correct password"
OK
(From now SIM Card is locked and PIN is requested on power up)
AT+CLCK="AB",0,"incorrect password"
+CME ERROR: INCORRECT_PASSWORD
AT+CLCK="IR",2
+CLCK: 0,1
+CLCK: 0,2
+CLCK: 0,4
OK
AT+CLCK="IR",1,"correct password" //<classx> is defaulted to 7 when not specified
OK
AT+CLCK="IR",2
+CLCK: 1,1
+CLCK: 1,2
+CLCK: 1,4
OK
AT+CLCK="OI",2
+CLCK: 0,1
+CLCK: 0,2
+CLCK: 0,4
OK
AT+CLCK="OI",1,"correct password"
OK
(All international calls are barred.)
AT+CLCK="OI",1,"correct password",3
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