TMC (Traffic Message Channel)

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November 2010 Update:

TMC for Dublin is now live, please visit your Sat Nav manufacturers website to check if map updates are available for your device. If purchasing new devices check that the maps are up to date with new maps of Dublin.

Following a series of traffic improvement schemes in the City Centre, Dublin City Council is playing a key role in a new Traffic Information Service to help motorists find the best routes in the city.

The service is based on RDS-TMC (Traffic Message Channel) technology, a universal standard widely used across Europe, but not, until now in Ireland. Unlike existing traffic bulletins, TMC messages appear on the user’s satellite navigation device, showing not just the nature of the traffic problem, but also its exact location. What’s more, the navigation device can avoid these traffic problems when calculating a route to the desired destination.
The TMC service can also inform motorists of closures at the Port Tunnel or let them know when the College Green Bus Priority is in operation. Weather warnings can also be included.

The broadcasting service is provided by RTÉ Networks Limited. At launch the service will be available to motorists in the Dublin City Council area, and will be rolled out to cover the entire country shortly afterwards.
The Traffic Control Centre at the City Council will be the main source of traffic information for Dublin. With access to more than 200 cameras, the City Council has the most accurate and up to the minute picture of Dublin City traffic.

The TMC service will be available to users of enabled satellite navigation devices and integrated car navigation systems. Many existing users will also be able to update/upgrade their device or navigation software to receive the TMC service. The TMC service will be free at the point of use, with enabled devices coming with a lifetime subscription to the service. The use of TMC abroad (where available) is also free of roaming charges.

Frequently Asked Questions (FAQ's) about Traffic Message Channel (TMC)

1.I have a Sat Nav device already, Will TMC work on it?
Not as it is, but you will most likely be able to download an update. The technology used in TMC requires the manufacturer of a Sat Nav device to implement a service specific database into their maps and software. Contact the manufacturer/retailer about the availability of an upgrade containing those databases.
In addition, you may also need to purchase a traffic receiver, which is in effect a special radio receiver that can decode RDS-TMC data. 

2. What do I need to do to get TMC to work on my Device?
Contact your manufacturer/retailer about the availability of an update. Please bear in mind that it may take some time until such an update is released commercially, as enabling a device is a complex task and some manufacturers, particularly in the automotive industry apply quite long update cycles (e.g. some release only scheduled updates only twice or even once every year).

3. How much will it cost to upgrade?
If the update involves only the software update to enable the device for traffic, the update will be free of charge. However, some devices will also require a map update. This means that apart from enabling the device for receiving TMC traffic information, you will also receive the latest map (e.g. a map that already included the new Samuel Beckett Bridge in Dublin) database. Depending on your original purchase deal, some manufacturers will charge you for the map update – but if they do, they would also charge you even if the update did not include traffic.

4. Do I need any other equipment to receive TMC broadcasts?
As RDS-TMC has not been previously available in Ireland, several manufactures sold devices without a traffic receiver, thus reducing the initial cost of their device. (Devices with Ireland and UK only maps are more likely to have been sold like that than devices with full European mapping.) To enable such a device for RDS-TMC, apart from enabling the software, you will also need to purchase a TMC traffic receiver. The typical cost is €30-50, depending on the manufacturer.
In some cheaper or older devices it may be impossible to connect such a traffic receiver, in which case the entire unit will need to be replaced.

5. What is TMC?
TMC stands for Traffic Message Channel, a digital data stream that informs the satellite navigation device about road closures and congestions. These messages (or traffic alerts) are carried as part of the RDS data by FM radio stations and are regularly downloaded to the device. The downloaded traffic alerts are then used by the navigation application to recalculate your travel time and, if available, plan an alternative route avoiding those problems.

6. Why can’t I always receive TMC alerts?
TMC coverage is smaller than that of the radio programme carrying the TMC service, therefore white spots do exist. Reception can also be affected in built-up areas. 

7. Will I incur roaming charges if I use TMC abroad?
No. All TMC services available on your device are provided as part of a lifetime subscription that came with the device. You will not incur further charges whether you use TMC in your home country or abroad (where available).