How many light modes does Trek CarBack Radar Rear Light have?
Trek CarBack features four modes – Day Flash, Day Steady, Night Flash and Night Steady modes.
Trek CarBack Radar Rear Bike Light
Trek CarBack features four modes – Day Flash, Day Steady, Night Flash and Night Steady modes.
Pressing and holding the power button for one second powers CarBack on and off.
Yes, a quick press of the power button will temporarily activate the power status LEDs showing the battery status.
The stated battery life is 7 hours. Battery life can vary depending on the activity of the Radar system and number of rear-approaching vehicles identified by CarBack while riding. The actual battery life will often exceed the stated battery life.
CarBack will generally take 3.5–4 hours for a full charge with the included USB-C charging cable. The charging time is dependent on the power source and can vary.
USB-C, a USB-C charger cable is included.
CarBack has an IPX7 waterproof rating.
When installed correctly and under ideal conditions, CarBack can detect rear approaching vehicles from up to 240m. ANT+ protocol for radar does have a limit of 196m, so a Bluetooth connection with a phone running the Trek Accessories App is required to realize detection distances beyond 196m. It is also worth noting that some third party apps plug-ins for GPS head units have limits to the reported distances that they will show, even if actual detection ranges are longer.
To reset the CarBack to your factory settings, you hold the power button for 15 seconds. CarBack will flash once at 8 seconds and again at 15 seconds, indicating that the factory default settings have been restored.
The Trek CarBack can detect vehicles, motorcycles and cyclists depending on their size, location and travel direction relative to the rider.
Most GPS cycling computers are compatible. CarBack uses universal ANT + protocol to communicate to GPS cycling computers and watches. See the full list of ANT+ compatible devices here
ANT+ compatible devicesYes, Trek CarBack works with the Trek Saddle Accessory Blendr mount as well as several bike model-specific integrated Blendr light mounts.
No, CarBack and the Blendr Fendr are not compatible.
We do not recommend helmet-mounting Trek CarBack. Trek CarBack works best when securely mounted to a fixed part of the bike, ensuring the most consistent operation and detection of rear-approaching vehicles.
Trek CarBack is a proven Daytime Running Light and can be seen from up to 2 km during the day.
We always recommend ensuring that your GPS unit is running the latest firmware version for the best experience. There were some now outdated firmware versions that inhibit certain aspect of Radar and CarBack functionality. Check with your GPS Head unit manufacturer for the latest firmware for best experience.
Yes, you can plug CarBack Radar into an external battery bank while in use to extend the battery life. It will turn off when you plug it in, but you can then turn it back on again for use while charging.
Radar is the largest driver of battery use, far greater than the flash of the light. We officially state runtime as 7 hours in all modes from the 2,000 mAh battery, but again it is radar-dependent. Seven hours would be worse-case, with Radar constantly working and being the main driver of the battery. When no cars are being picked up by the radar, the radar goes into battery-saving mode and provides significantly less battery draw. This significantly extends battery life and is the case for most normal riding conditions. We are generally seeing up to 12 hours of run time in average riding conditions on day flash mode.
Trek Accessory App
Yes, Trek CarBack can be paired with a phone with the Trek Accessory App (iOS and Android). The app will display approaching vehicles and can also inform riders of approaching vehicles via audio alerts.
Vehicles recognised beyond 150 m/500 ft will show as static triangles below the 150 m/500 ft line. Once these vehicles are closer than 150 m/500 ft, they will appear as approaching vehicles on the screen.
After downloading the Trek Accessory App, tap ‘Get Started’. Follow the on-screen instructions to locate and connect to your CarBack radar. Be sure to allow any Bluetooth connection prompts and verify your phone’s Bluetooth is turned ON. Select your CarBack radar and it will begin pairing with your phone. After connecting once, the app will automatically pair with your CarBack radar on your next ride.
No, the Trek Accessory App is designed to work only with the Trek CarBack Radar Light.
Yes, connecting your CarBack device with a Garmin or Wahoo head unit via ANT+ and the Trek Accessory App via Bluetooth, at the same time, is possible.
Yes, the Trek Accessory App can provide audio alerts while running in the background. If you turn off your screen or put your phone to sleep with the app running while connected to CarBack, you will continue to receive audio alerts as to your set preferences.
If you have sounds enabled and your phone is not muted, the vehicle alerts from the Trek Accessory App will match your phone’s volume setting. If you want louder or quieter alerts, adjust the volume of your phone.
Bluetooth permissions are needed for the app to connect and communicate with the CarBack device.
Yes, multiple GPS units can all connect to a single CarBack unit and all get the same alerts delivered.
Dual axis detection refers to CarBack’s ability to identify not just the distance behind the rider of an approaching vehicle, but also whether the vehicle is directly behind the rider or to the left or right of the rider. This features requires use of the Trek Accessory App.
At a distance of 75 m, CarBack is able to determine a vehicle’s relation to the rider in both x and y distance and show it visibly via the Trek Accessory App.
No, the Trek Accessory App is required to display approaching vehicles and their positions relative to the rider on both the x and y axes.
If you're on the Ride Screen and no vehicles are detected, your screen will auto-dim to save battery. When a vehicle is detected or when you tap the screen, your phone will return to normal brightness.
At this time, the flash pattern cannot be adjusted via the app.