Cisco 2500 WC and the General Motors MDI Device

 

We have these vehicle diagnostic devices called MDIs. Service technicians use them to connect to vehicles and do remote diagnostics on them. They are connected to the wireless mesh and transmit the data back to a local pc somewhere in the network.

A couple things:
The wireless network needs to have BROADCAST enabled in order for these devices to work. The devices send out a broadcast to the network, which in turn is picked up by the service PC’s and they send/receive data. The Cisco 2500 WC that I’ve got, by default, has broadcast disabled.
Info here and here
The basic of it is this:

In the CLI of the WC, send this command: CONFIG NETWORK MULTICAST GLOBAL ENABLE

Of course General Motors has no idea this is how it connects.. 2 days on the tech line with them yielded no results. I took a guess on this one and won.