In summary, these were what I needed to unlock my AT&T Sierra Wireless
754S (or aka AT&T Mobile Hotspot Elevate 4G).
(1) Unlock code from AT&T
(2) A non-AT&T SIM card, which needs to be inserted in the device to
(3) A Windows XP computer to use HyperTerminal. AT&T also gave
an option to unlock it through AT&T Connection Manager, but it does
not work for this device.
(4) By the way, the instruction from AT&T was wrong and full of
errors. I had to figure the correct commands.
I was using AT&T Sierra Wireless 754S, also known as Mobile Hotspot
Elevate 4G, until I purchased my iPhone 5S last July. The unit
has been disconnected since then. But, it came to my mind that
the device may be useful if I unlock it. I can lend it to a
short time visitor, for example. We often have a visiting
scholar from Japan. A network connection is always an issue.
I can lend this device to a visiting scholar, and he/she can buy a
pre-paid SIM card.
I first tried to send an unlocking request by myself from the AT&T web site.
The IMEI number of the device (which can be found behind the battery
on this device) was rejected. The error message implied that my
IMEI number was not in their database.
I called AT&T customer support and asked to unlock it. The
first operator was sloppy and sounded like she was not willing to
help. In fact, she said she created an unlocking request, but
later turned out she did nothing.
Since AT&T did not get back to me with the confirmation after several
hours of the first phone call, I called again. The second
operator was professional. In fact, she really tried to help me.
She said there was no record of the unlocking request on my account.
That's how I figured that the first operator lied.
What she figured was that the AT&T database looked to be screwed. I followed her instruction, but the web site still said
it didn't recognize my IMEI number. Then she looked at my
account record and confirmed that the
IMEI number was correct. She also tried to send an unlocking request from
her side. But, she also had the same error indicating that the IMEI
number was not recognized. At that point, what I knew was that
there is a record of my device on my account. However, the
device cannot be recognized from the unlocking-request page. She
raised an issue to a higher-level tech support, and I was supposed to
get a reply by Wednesday.
As I expected, I heard nothing by Wednesday. I called again, and
a very fast-speaking operator took my call. He said that the
request was approved on Monday, and an E-mail was already sent.
But, the E-mail was nowhere (in my mailbox) to find. He tried to
walk me through the steps. But, to unlock this particular
device, I needed a PC, and he was not a very good PC tech support.
I asked him to send the content of the E-Mail over the text message,
and I finally got the instruction and the unlock code for my Elevate
The instruction showed two options. One is with AT&T
Communication Manager, and the other with HyperTerminal. The
first option didn't work. I have tried AT&T Communication
Manager versions 7.2.32 and 9.2.359.7, both of which did not recognize
my Elevate 4G.
The second option was full of errors. First, Windows does not
recognize the Elevate 4G as a modem. However, the instruction
was assuming that Windows was going to recognize it as a modem.
I needed to identify which COM port is assigned to the device, but
this instruction didn't help. Instead, what I had to do was to
open the device manager, and open Port (COM & LPT). It indicated
that "Sierra Wireless AT Command Port (UMTS)" was assigned to COM6.
That's what I needed to know.
By the way, since Windows 7 and 8 does not include Hyper Terminal, you
may want to pull out your old Windows XP machine if you are in the
same situation. Make sure your Windows XP is disconnected from
the world. Sierra Wireless drive is installed from the device's
own storage, and all you need is Hyper Terminal. Nothing to
download from the Internet. I could download a free terminal
program for Windows 8, but I didn't want to install a program that I
almost certainly won't need after unlocking. I just fired up one
of my Windows XP machines. (In fact, I tried AT&T Connection
Manager on this PC, too. I didn't want to contaminate my working
PC with a one-time-use programs.)
Use "Device Manager", not "Phone and
Modem" to identify the COM port number.
Then, next issue was HyperTerminal. There is no such thing in
Windows 8. I ressurected an old Windows XP laptop, which has
been disconnected from the outside world when it was no longer
supported. I connected my Elevate 4G with the USB port, and
opened Hyper Terminal (from Start Menu > Accessories). I had to
create a new connection. Just gave a random name, and then
Give a random name and pick one of
Select the number from the Device
I followed the instruction, and typed ATE1<enter> and the device
replied with "OK". By the way, you may not see the echo back of
"ATE1" for the first time. The command "ATE1" enables echo back.
So, for the first time, you may need to type it blindly.
to enable echo. AT commands reminded me of the days of 2400bps
Then, the AT&T instruction told to type
where aaaaaaaa was the unlock code from AT&T.
THIS WAS WRONG!
Actually, this was wrong in two ways:
(1) Correct command needs double quotes as: AT+CLCK="PN",0,"aaaaaaaa"
(2) You need to type this command while a non-AT&T SIM card is in the
I was getting errors until I added double-quotes like below.
This command given in the instruction is
By the way, I crossed the unlock code so that you don't even try this
number. You need to get this number from your original carrier,
in my case AT&T.
YOU HAVE LIMITED NUMBER OF UNLOCKING
ATTEMPTS BEFORE YOUR DEVICE IS PERMANENTLY LOCKED.
The number of allowed failure can be as low as five times. Make
sure you get this number from your carrier.
Then, I added double-quote, but I got a different error because the
original AT&T SIM card was in the device.
The device was thinking it was not locked
and therefore cannot be unlocked because I still had the original card
from AT&T in this attempt.
The first command was to check if the device was locked. What's
weird was the reply +CLCK: 0 was supposed to mean the device was
unlocked. I anyway went ahead and tried to unlock it, and got
At that point, I suspected that I might need to install a SIM from a
different carrier. The unlocking command may have failed because
the device was thinking that it was not locked. By inserting a
SIM from a different carrier, the device may think it was locked.
I had a T-Mobile nano SIM that was good for activating a phone (with no
data and talk time). I cut a piece of plastic so that I could
scale-up the nano SIM to the full-size SIM. I inserted my
scaled-up T-Mobile nano SIM and tried again.
My nano SIM to full-size SIM adapter.
First, I checked if the device was thinking it was locked by typing
AT+CLCK="PN",2, and +CLCK: 1 indicated it
actually was locked. Then I entered the unlocking
command, and I got a reply OK from the device. As soon as I entered the
command, "SIM MEP Locked" message was gone, and my Elevate 4G was
communicating with T-Mobile network.