Invalid Unit

Let's try add an additional number so that the unit has some information to download. 

1. We start by dialling *#0007, *#0004 from the cellphone number of the intercom.

2. Wait 5 minutes and then test again by dialling *#0003

3. Send an SMS with the word “Reboot” to the cellphone number of the intercom.

4. Wait 5 minutes and then send an SMS with the word “Update” to the cellphone number of the intercom.

5. Wait 10 minutes and then dial *#0003 to test again.