title: How to change/create SIM PIN using AT commands when the SIM card has no PIN?
body: <p>I'm using a SIM868 module and I was using my usual SIM card with no problem, but now I have bought a new SIM card and has no pin. I need to add a  PIN code in order to have more security.</p>
  
  <p>I have checked that it has no PIN enabled using this command: <code>AT+CPIN?</code>.</p>
  
  <p>and the answer was: <code>+CPIN: READY</code>. </p>
  
  <p>I have searched how to change it in the SIMCOM's AT commands manual and I have found 2 options: </p>
  
  <ol>
  <li><code>AT+CPIN=&lt;pin&gt;[,&lt;new pin&gt;]</code></li>
  <li><code>AT+CPWD=&lt;fac&gt;,&lt;oldpwd&gt;,&lt;newpwd&gt;</code></li>
  </ol>
  
  <p>I have tried both of them, but in the first one I can't insert the actual PIN, because there is no actual PIN. And in the second one I have tried different commands due, in the description of the AT command,  sais <em>"If an old password has not yet been set, <code>oldpwd</code> is not to enter"</em>. None of this ones has worked (guess that 1234 is the new PIN that I want to use)</p>
  
  <pre><code>1) AT+CLCK=“SC”,"1234"
  2) AT+CLCK=“SC”,,"1234" 
  3) AT+CLCK=“SC”,“”,"1234" 
  </code></pre>
  
  <p>The answer to that 3 cases was the same: <code>ERROR</code>.</p>
  
  <p>(If someone is going to suggest that I can change or try the SIM card with a mobile phone I can't do it because this new SIM card is a miniSIM card and all my phones use nanoSIM or microSIM).</p>
  
  <p>Any suggestions?</p>