Wavecom Q2303A

Hello all.

I have recently bought this Wavecom Q2303A-GSM modem, and it has a small disadvantage:
When connected to the computer during startup (the computer’s startup) the modem sort of freezes with the red light permanent on, and most AT-commands only gives the response ‘ERROR’.

Disconnecting the device and reconnecting it does not solve this. Only way to get it to work is: Disconnect the modem, remove the SIM-card and put it into a cellphone, turn this phone on and off again, and put the SIM-card back in the modem. Now, when connected, the modem works.

If it is possible, I’d like to know what the cellphone does, and how to make the Wavecom Q2303A-modem do the same.

There is a little mystery about this modem however: The ‘Wavecom Q2303A’ doesn’t seem to exist. Or ever have existed, according to this thread: /viewtopic.php?f=118&t=7377

But nevertheless, this exact modem is floating around all over the internet, being sold everywhere… :question:

Sincerely/Best regards
Mads Aggerholm


Can’t help about the modem specs.

However, are you using a Windows PC?

Windows has a nasty habit of assuming thay anything connecter to a serial port at boot time MUST be a serial mouse and fires of a bunch of commands to it to the serial device. I’ve run into this issue with serial gps modules… I wonder of windows is sending sending some rubbish to the serial port that is locking up yput modem.

You could try sending a atz to reset the modem after it has locked up.

Ciao, Dave

What “Wavecom Q2303A-GSM modem”? Where did you buy it? Didn’t you get any documentation or support with it :question:

I think this is a very, very old product from waaaay back when Wavecom made an unsuccessful attempt to get into the cellphone market?
They probably only made it - and its documentation - available to selected “partners” only :question:

But only as surplus, unsupported stock

It certainly does :exclamation: :angry:

There are ways to disable this - google will help…


Just to clarify:

Should be

You can tell that this is happening if you are getting random mouse movements on the screen.

ciao, Dave

Actually, I think you were right the first time?

I think Windows actually searches COM ports - ie, sends some query to each COM port - to see if any serial mice are connected :question:

And it’s that query which messes-up your modem.

Again, it can be disabled…

Hello again.

Thanks for the answers, everybody.

Dave: Thanks for the clearance about WIndows behaviour at startup. ATZ does not work, however. The red light stays on, and the modem responds only to very few commands. CMDR and CMDS is not among them…

awneil: I got a CD with some chinese writing - the names of the folders and files were in chinese(!!) Never seen that before… And it could not be used for anything, the computer said it could not find certain folders.
So, waaay back? Sounds like this modem is quite obsolete, huh?

davidc: No random mouse movements. But trying to disable this is worth the try.

I have now had the modem lying disconnected for a couple of days, but when connected again (to a running computer) it continues with the red light permanent on.
When I take out the SIM-card (and do the put-the-sim-card-in-a-cellphone-trick) and put it back in, the modem starts working.
I still don’t get it. It’s like something is stored on the card itself, telling it to misbehave. Otherwise I’d think disconnecting the modem an connect it again after a few seconds should make it work.

I fell like throwing in the towel, and get another GSM Modem.
Can anybody recommend one?


You haven’t got a sim pin set on the SIM card?

You can check by putting the sim in the modem and using


It’s interesting that you got a dodgy cd with useless documentation. You’re one up on the last poster who had one of these.

For another modem, have a look at the FXT range.

Ciao, Dave

Yes - very much so.

I don’t think you necessarily get them; Windows might decide from its probing that it’s not a mouse - but it’s the probing that upsets the modem!


SIM operating voltages have changed a lot since this device was current. Seems a bit of long shot, but…

Unless you have a really compelling reason to use it, I think it’s of historical interest only. Anything you try to do with it is likely to be limited by its (lack of) capabilities.
It might not even do GPRS…

What do you actually want to do with it :question:

Do you really want a Modem - ie, a cased product - or an embedded module :question:

Hello again,


Nope! I turned it off, exactly because I didn’t want to fumble around with that.
And when the SIM-card is inserted into a normal cellphone, it start up instantly. No problem there.


All I need is to send and receive SMS messages with my PC. I have done it for a copuble of years using a Siemens TC35 which have done an excellent job.
However, I needed a new computer for the purpose, and new computers have no RS232-port. I thought switching to USB should be the right way to do it.

So no need for a new modem - just use a USB-to-RS232 adaptor :exclamation:

So how does this Q2303 help with that? It surely pre-dates USB by many years!

GL6110: sierrawireless.com/productsa … eries.aspx

But, if your PC has internet, you don’t need a modem at all - just use a “gateway” or “bulk SMS” service 8)


Just out of interest, I was using DWLWin this morning, and noticed that there was an entry for the Q2303 in the ‘Airprime Type’ dropdown box. The entry is Q2403/Q2303/Wismo2

So it did exist some time ago … maybe the SiWi team can trawl through the old Wavecom Archives that used to be available on the web and recover the AT commands guide for this device.

As has been mentioned before, these things are for sale all over ebay and the internet in general…

ciao, Dave

I got one. The thing is, it is not very stable.

The Q2303A-modem I bought has a USB-connection… ?

Unfortunately, this is not an option. It is made for a security system, that must not depend on access to the internet.

Nice one. But does it just plug in and are ready to do the SMS-business using AT-commands?