Harley-Davidson's Canvidon: HDLAN communications system: HDLAN

In this article we will try to explain in a simple way the last communications system of Harley-Davidson, the HDLAN.
This new technology will allow the entire H-D range to have ABS brakes, lower wiring and the removal of the contact key among other improvements.

Internet inside your motorcycle
One of the first questions you can ask when you hear the communications system is why does this need a motorcycle? The answer must be sought in the technological evolution to which automotive brands have been forced in recent years to reduce emissions and meet the increasingly demanding regulations and at the same time improve safety standards and driving quality.
With the adoption of electronic injection, it is necessary that the different sensors and actuators communicate with the ECM or vehicle switchboard.
This communication is produced in digital language, that is, with "zeros and some", just like our personal computer or a tablet.

Let's give a simple example:
-The pilot acts the left flash switch.
-The module of the handlebar buttons launches the message "Intermittent button" to the network.
-The BCM (Electric Controller) Reads this message and energizes the flashing of the indicated side, also looks for the velocimeter signal and also that of the inclination sensor, in this way determines how long the intermittent will remain on.
-At the same time the speedometer also reads the message and ignites the control intermission witness.
All these messages are sent through a cable, called the “data bus”, which is a kind of the Internet inside the motorcycle, which allows the modules to be communicated to each other.

Hdlan
Until 2011 the communications protocol used 1 cable and was based on ES standard J1850. As of this year, a faster protocol, with 2 communications cables, the HDLAN, based on the Can Bus automotive standard, began to be used in the Softail models.

Not to lose yourself in technical details, imagine that J1850 is like the Internet based on the RTB telephone line, ancient and very slow. On the other hand, the can bus would be like the ADSL, faster and more modern.

With the use of the HDLAN communications system (Harley-Davidson Local Area Network) several advantages are obtained:
-Mayor data speed
-Mayor data loss security
-Reduction to the minimum expression of wiring, relays and fuses on the motorcycle

-It more compact and unified modules
-In improved diagnostic capital

The heart of the system is the BCM, a module that the battery energy receives directly.

In the models prior to this system if we pressed the horn button for example, what we did was connect the battery energy with the horn so that it sounds. The electricity went from the battery to the handlebar button traveling the entire motorcycle and then lowering from the button to the horn.
With Hdlan when we press this button, what happens is that it is "published on the Internet of the Moto" that we want the horn to sound, so the BCM reads the message and sends the electricity directly to the horn to sound.

There is no electricity up and down the handlebar to activate it, just a message. This applied to the entire motorcycle electrical system means that all modules (speedometer, ABS, BCM, ECM or switchboard, radio ...) can communicate with each other with which higher performance and reliability are obtained.

Improvements such as those that have appeared in Sportster models as the possibility of knowing the revolutions or the march to which we circulate in the accounting, the introduction of the ABS, the disappearance of the contact key and the optimization of the battery compartment are possible thanks to this technology.

Conclusion
It is evident that Custom models owners are not the greatest fans of technological sophistication, but knowing that it will inevitably wrap our lives (and our motorcycle), at least it is comfortable to know that in some cases it is used to simplify complex systems, making them at the same time safer and more reliable. This magical mixture of Old School & New Technologies is produced, which will keep us rolling free and better communications.

Frank Burguera

#mecanicaharley