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The EcoRoute HD is a small module about the size of a deck of cards that features a short OBD-II connection pigtail extending from one its ends. The pigtail simply plugs simply into the diagnostics port located, in most vehicles, under the dashboard in the driver's foot well. In the package, users will find a few long zip ties that can be threaded through channels on either end of the device and used to anchor the unit in place. The HD features a pair of LED status lights on its top side, one green and one blue, that illuminate to indicate the unit's connection status with the vehicle and with the Garmin GPS device. There is also a small reset button that can be used to restore the unit to its factory-fresh state in the event of a malfunction.
After connecting the EcoRoute HD to the vehicle, simply start the engine and wait for the LED status light to blink three times to indicate that it is ready to connect to a compatible Nuvi device. We used the Nuvi 1490T for our testing. From the Nuvi's menu, we selected Tools, then EcoRoute, at which point we were asked to answer a few questions about our vehicle to initiate the EcoRoute software. Once through this wizard, we were presented with a button in the bottom status bar for HD connection. (If your Nuvi doesn't present this option, update its software and double-check that it is a supported model.) After a few more onscreen prompts, our Nuvi and EcoRoute HD module were paired.
Features and performance
The EcoRoute HD utilizes Bluetooth for its wireless connection to the portable navigation device, so it only has a maximum line of sight range of about 30 feet. Tucked under our dashboard, surrounded by metal, we found that we could only get about 10 feet before losing our connection. That said, 10 feet is more than enough range for in-car user.
When both the EcoRoute HD module and the paired GPS device are powered on, the HD module will beam detailed data from the vehicle diagnostics system to the Nuvi device. The Nuvi then processes that data to display live information to the driver. Most drivers will find the system's ability to more accurately track instantaneous and average fuel economy, as well as carbon footprint, useful. The Nuvi will also use this information to create a driver challenge score that summarizes how efficiently the vehicle is being driven. However, having nearly unfettered access to the car's brain allows the EcoRoute HD to provide much more data than we think the average user ever needs.
Other available monitored parameters include intake air temperature, coolant temperature, throttle position and engine load, intake manifold pressure, battery and charging system information, mass airflow rate, timing advance, and emissions data. While most of this will likely sound like geek-speak to the automotive layman, car nerds and shade tree mechanics will find this sort of depth of information to be useful (or at least interesting).
For trips where GPS navigation isn't necessary, people needn't worry about going through the trouble of powering up their Nuvi. The EcoRoute HD module will continue to monitor and cache vehicle data, even when it's not connected to a GPS device, and upload all of this info on the next successful connection. In addition to acting as a high-tech gauge cluster, the EcoRoute HD module also enables users to view vehicle trouble codes. When the check-engine light comes on, users can access a menu on their Nuvi and receive the OBD system's code for what's causing the problem. These codes are usually related to the vehicle emissions system and can help identify anything from a malfunctioning sensor to a misplaced fuel cap. However, more serious issues can require the assistance of a mechanic. Once the issue is resolved--for example, you replaced that lost gas cap--the Nuvi's menu can be used to clear the trouble code and reset the check engine light, saving a trip to the shop (and potentially keeping money in your pocket) for simple fixes.
We found the EcoRoute HD to be quite useful accessory for the small slice of Garmin's Bluetooth-enabled Nuvi lineup with which it is compatible. The gearhead in us loved having access to the information overload of engine parameters and being given the ability to diagnose and fix small problems on our own. The treehugger in us loved having a tool that helped us to monitor our carbon footprint and improve our driving efficiency.
However, there are a few odd stacked against the EcoRoute HD. Firstly, it's only compatible with a few Nuvi devices. More units will be added in the future, but this limitation already cuts the HD off from a large number of users. Additionally, more and more modern vehicles are beginning to feature increasingly sophisticated fuel economy monitoring functions in their trip computers, which could make the EcoRoute HD seem a bit redundant to, for example, your average Prius driver.
Finally, due to inconsistencies in data reported over the OBD-II connection, there exists a subset of vehicles that could end up reporting inaccurate data to the EcoRoute system and a few vehicles that are simply incompatible. Garmin maintains a list of these vehicles on its Web site, but you'll probably want to hang onto your receipt for a few weeks just in case your car is an unlisted dud.
While we feel it is important to point out the EcoRoute HD's shortcomings, we do feel that--as a tool--the pros far outweigh the cons. If you already own one of the compatible Nuvi devices, the $99.99 EcoRoute HD has the potential to pay for itself over time in fuel savings--perhaps sooner if it saves an expensive trip to the mechanic over a simple fix.