Databus Modules - Get On The Bus - Truck Tronics

  |   Databus modules like this Directed Install Essentials combination door lock and bypass model can cut hours off installation time. As far as installing a security or remote-start system on your truck goes, depending on what make and model you drive, you might have an install that is fundamentally seamless and effortless-or it could be a bear and a hard slog for your installer. Whether or not your installer can integrate with databus makes the difference. In issue No. 3, we discussed how factory databus relates to your stock head unit. The average car or truck has 70 different computers onboard, linked by databus, running an astounding 35 million lines of software code. Automakers use multiplex wiring (sending multiple digital signals over the same wires) to save weight and cost and to facilitate the computer control of functions like engine management and transmission control. These in-vehicle networks are complex, and glitches occasionally pop up. According to the Los Angeles Times, automakers spend as much as $3 billion a year fixing software issues to make their databus systems more reliable, because approximately one-third of all vehicle warranty claims are related to electronics or software. But the automakers are not the only ones riding the 'bus. Vehicle security and remote-start installers have an ardent interest in databus, because having a module from companies like Directed and Trilogix that both reads and writes to the databus can mean the difference between an easy one-hour install and a painful three-hour install-and one or three hours of labor costs passed on to you. "Any time we can avoid removing door panels to integrate with the power locks, that's a benefit," said Kevin Willard, mobile electronics instructor at The Snake Pit installation training school in California. "It definitely benefits consumers to avoid unnecessary disassembly of the vehicle. We recently spent several hours at The Snake Pit with Willard, a 21-year veteran of the industry, as he demonstrated our options-with and without databus-on an '03 Chevy Silverado. "When I started in this business, it wasn't nearly so painful to install alarms as it is today," he said. "The difference is data." In order for the alarm to also provide power door lock/remote keyless entry functions, it needs to integrate with the door computers, and there are two ways to do that: an easy way and a hard way. After carefully removing the driver-side door panel, Willard quickly and methodically tied four diodes and two relays into the door's computer wiring with cutting, splicing, and soldering. This part of the install also involved 10 connectors for the relays, plus four more for the diodes if the installer doesn't solder. Keep in mind that every connector without solder is a potential failure point. Total time for this expert installer to complete the driver's door installation? Approximately one hour, which would then be repeated on the passenger door, and then at the Body Control Module (BCM). By contrast, the installation of the appropriate databus module was simple. It involved connecting power and ground and then connecting a single wire to the GM databus. This is followed by a one-minute procedure where it "learns" the vehicle, during which the module recognizes the specific model year of that particular vehicle and then broadcasts the appropriate digital "words" onto the bus, commanding the door computers to lock and unlock the doors when the user pushes a button on a remote. Total installation time: 25 minutes. "Most vehicles are just a pain without databus, but some absolutely require it, like the VW Toureg and Porsche Cayenne, which operate on the CAN 'bus-CAN data is just now becoming available to us," said Willard. "No one at the automakers is saying 'I wonder how we can make things easier for the aftermarket.' It's up to the aftermarket to keep their research and development as close to the cutting edge as possible, so we can continue to customize the electronics on new cars and trucks. The bottom line for consumers? Next time you go shopping for a security or remote-start system, ask the installer if there is a databus module for your vehicle. If there is, that's your cue to hop on the 'bus!