Can't define a new PIN

I have a brand new SIM card. This card came without a PIN, the provider confirms this: initially all their new cards don’t have a PIN, if I want a PIN I should configure one in the Settings.

I tried this. Under Settings | Security | SIM card lock.

There’s only one option executable “Lock the SIM card” with the sub text “phone can only be used with a PIN” - yes, that’s what I want. The other option “Change PIN for a SIM card” is gray.

But when I try “Lock the SIM card” it wants at first a PIN, I guess that’s the “old” PIN which should now be replaced. But I have no old PIN. When I press OK here without specifying a PIN it says I have only two attempts left. I don’t want to use these two attempts for reasons.

What can I do to get a proper PIN onto my SIM card?

My guess would be that the SIM card does actually come with a default PIN.

A few default PINs are shown

Some carriers publish their default PIN like

Samsung offer this including the “fail option” advice:

Once SIM has been blocked, it will request for PUK code.

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Thanks a lot for the advice. Seems that I must indeed ask the provider for the concrete steps and about a possible default PIN.

Ha, the provider lists this problem in a FAQ and blames the device:


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I tried now to use separate GSM-modem (Telit) responsive to Telnet and a so called AT command set. These devices have a SIM card and provide receiving and sending of SMS controlled by a PC.

First idea was to use the ordinary +CPIN command because this would allow to set a new PIN using the PUK. But +CPIN requires that the device is in expectation of a PIN. In my case the device answers on AT+CPIN? just with READY, it doesn’t expect a PIN, never. So +CPIN will not work (and indeed it doesn’t, I tried this).

There’s also +CPWD for changing a password (this can be the SIM PIN) especially in the case that you are already logged in. But +CPWD doesn’t require the PUK but the old PIN when you want to set a new PIN. Indeed commands without an old PIN like AT+CPWD "SC",,1234 or AT+CPWD "SC","",1234 fail also consequently.


Maybe these cards are not intended to be pin-protected, at all? :astonished:

Of course i have not the same carrier as you, and i am not in the same country, but as far as i remember all the default code for the 6 SIM i got in the past were 0000.
I hope it will be helpfull.
Most of the time, the PUK is noted on the SIM support

I nailed it somehow. I used again /e/ as in my opening, but I entered the PUK instead of that missing old PIN. This was somehow the key! Who knows that??? Than I came into the same screen with the numbers known from entering a PIN and I had to define the new PIN and to confirm it, than it was valid. I have indeed my desired PIN now. But this all was based on guesses and it took me an entire day (OK, I was also doing other stuff). Thanks for reading all.