Honeywell L5100: Find the MAC and CRC of the system's communicators

The MAC and CRC are needed when you are signing up for monitoring. See how to find them in this short video.

Related Products

Honeywell LYNXTOUCH L5100 - LYNX Touch Wireless Alarm Control Panel
Honeywell L5100
LYNX Touch Wireless Alarm Control Panel

Related Categories


This video is about Setting Date and Time on a Honeywell L5100


Hi, DIYers, Sterling from Alarm Grid here, and we're going to show you how to find the MAC and MAC CRC information from an AlarmNet Communicator that you may have installed in your LNYX Touch L5100 system. For those of you that aren't familiar with AlarmNet, that is Honeywell's Alternative Communication Division. They supply the communicators and the alarm monitoring services that people can use, so that they do not have to use a regular phone line to have their system monitored.

With this LNYX Touch L5100, we actually have three options for alternative alarm communications. We have the L5100-WIFI, which is a Wi-Fi Internet communicator. We have the ILP5, which is a hard-wired Internet communicator. You would have to run an Internet cable from your router to your panel. The last option is the GSMVLP5-4G, and that is our 2G, 3G, and 4G capable cellular alarm communicator that would completely turn your system into a wireless system. No cable needed, and it uses AT&T's cellular towers to send the alarms to your central station. If you install one of these communicators, you're going to need to activate with an AlarmNet dealer, and that dealer is going to need your MAC and your MAC CRC from your communicator. They use that information to register and activate the communicator to turn your monitoring on, and that's how AlarmNet servers are able to talk to and receive signals from your panel.

If you were to sign up for our monitoring services with Alarm Grid, we're going to ask you for that information via email as soon as you sign up. And now we will show you how you can supply us that information.

If you hit more, tools, and enter your installer code, which is by default 4112, you'll be at the installer screen. You're going to hit program, and then on the right side we have comm diagnostics for communicator diagnostic. Hit that, and then we hit the down arrow. Then you have the option for communication ID numbers. If you do not have a communicator installed, you will not see these screens. Make sure to access these screens after your install it. If you try to do it before the communicator is installed, it will not show you these screens.

Hit communication ID numbers, and you can see at the top we actually have a Wi-Fi device and a GSM communicator for Dual-Path communications. You can see that we have our MAC GSM, we have our MAC Wi-Fi, and then, right below on the second line, we have MAC CRC, GSM, and Wi-Fi. The MAC will always start with 00D02D, and the CRC will always be a four-digit number. Simply write this information down, or send us a screen shot when you activate for monitoring, and that's how we will turn your system on. Once you have this information, to back out, you simply hit the back arrow, until you're ask to allow installer to re-enter programming. You always want to say 'yes' to this screen. You can hit the back arrow one more time to get to the home screen.

That is how to find the MAC and the CRC for your AlarmNet communicators. I will also mention that you can find this information on the box of any communicator, so if you buy a new one, it'll be on a sticker on the outside of the box. There's also a sticker on the unit itself. So if you didn't want to go through the programming, or you had it written down before, that's another way to supply that information. Please let us know it you have any questions on how to find or supply your MAC and CRC, and make sure to subscribe to your YouTube channel.