Secret Codes guide
**052*12345678*1234*1234# on iPhone: Unblock PIN2 With the PUK2
By Muhammad Shahid · · 4 min read
Quick answer
**052*12345678*1234*1234#: Clear a blocked PIN2 using the second unblocking key. PIN2 has its own unblocking key, the PUK2, entirely separate from the PUK that clears the main PIN. TS 22. 030 section 6. 6. 3 defines the procedure as **052*PIN2_UNBLOCKING_KEY*NEW_PIN2*NEW_PIN2#, and again a new PIN2 has to be supplied even if you only wanted to unblock.
Secret CodesDial codes, SIM & network test · Free on the App StoreDownload free →| Code | **052*12345678*1234*1234# |
|---|---|
| What it does | Clear a blocked PIN2 using the second unblocking key. |
| Published for | AT&T, T-Mobile and any iPhone |
| Type | Support varies |
Clear a blocked PIN2 using the second unblocking key. This page explains what **052*12345678*1234*1234# does, how to use it on an iPhone and which carriers it applies to.
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What does **052*12345678*1234*1234# do?
PIN2 has its own unblocking key, the PUK2, entirely separate from the PUK that clears the main PIN. TS 22.030 section 6.6.3 defines the procedure as **052*PIN2_UNBLOCKING_KEY*NEW_PIN2*NEW_PIN2#, and again a new PIN2 has to be supplied even if you only wanted to unblock.
A blocked PIN2 does not stop the SIM working for calls or data. It only locks the features PIN2 protects, which iPhone does not expose anyway.
Carriers are noticeably less consistent about issuing PUK2 than PUK. Some do not track it for consumer lines at all, in which case a SIM replacement is the only route.
Important: Ten consecutive wrong PUK2 entries permanently disable PIN2 and the functions it protects, and on some cards that state cannot be cleared at all. Only enter a PUK2 supplied by your carrier.
How do I use **052*12345678*1234*1234#?
- Open the Phone app and tap Keypad.
- Type **052*12345678*1234*1234# exactly as written.
- Press the green Call button and wait for the result.
Which carriers does this apply to?
| Published for | AT&T, T-Mobile and any iPhone |
|---|---|
| Type | Support varies |
| Good to know | Rarely needed on iPhone because iOS never asks for PIN2. Carrier availability of the PUK2 itself is inconsistent in the US. |
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Frequently asked questions
What does **052*12345678*1234*1234# do on iPhone?
Clear a blocked PIN2 using the second unblocking key. PIN2 has its own unblocking key, the PUK2, entirely separate from the PUK that clears the main PIN. TS 22. 030 section 6. 6.
What else should I know about **052*12345678*1234*1234#?
defines the procedure as **052*PIN2_UNBLOCKING_KEY*NEW_PIN2*NEW_PIN2#, and again a new PIN2 has to be supplied even if you only wanted to unblock. A blocked PIN2 does not stop the SIM working for calls or data. It only locks the features PIN2 protects, which iPhone does not expose anyway.
What are the steps for **052*12345678*1234*1234#?
1. Open the Phone app and tap Keypad. 2. Type **052*12345678*1234*1234# exactly as written. 3. Press the green Call button and wait for the result.
Where do I use **052*12345678*1234*1234#?
On the keypad of the Phone app.
Do I need to press Call after typing **052*12345678*1234*1234#?
Yes. Type it on the Phone keypad, then press the green Call button.
Is **052*12345678*1234*1234# a hidden or secret code?
No. It is a published service, not a hidden menu. iPhones do not have Android-style engineering menus.
Which carriers does **052*12345678*1234*1234# work on?
It is published for AT&T, T-Mobile and any iPhone. Rarely needed on iPhone because iOS never asks for PIN2. Carrier availability of the PUK2 itself is inconsistent in the US.
Is there anything to watch out for with **052*12345678*1234*1234#?
Ten consecutive wrong PUK2 entries permanently disable PIN2 and the functions it protects, and on some cards that state cannot be cleared at all. Only enter a PUK2 supplied by your carrier.
Does **052*12345678*1234*1234# work on Android phones too?
It is handled by the carrier or service rather than the iPhone, so it is not tied to one phone brand. Check with your carrier.
Will **052*12345678*1234*1234# work outside the US?
It is published for US carriers and services, so do not count on it abroad. Ask your carrier before you travel.
What if **052*12345678*1234*1234# does not work on my iPhone?
Check that it applies to your carrier first, because carriers decide which services they offer and can change them. If it should apply to your line, contact your carrier.
What is related to **052*12345678*1234*1234#?
**05*12345678*1234*1234#: Unblock a SIM With the PUK. Clear a PIN-blocked SIM using the unblocking key from your carrier.
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