Speedometer and Odometer
OneGauge includes multiple ways to get speedometer readings. Our standard recommendation is a GPS speedometer, which measures speed by satellite though an included antenna and requires no direct connection to the vehicle. Currently we offer a standard speedometer option that is ideal for daily driving, and an upgraded, race-spec GPS that updates 2-3x more quickly and will provide better results and accuracy for the sudden acceleration of racing or track use. Having the GPS option included also unlocks the ability to use distance timing (quarter mile, 0-60, etc) as well as custom lap timing when using OneGauge LCD screens. OneGauge can also source a speedometer reading from the OBD-II port, when available, or a can bus connection to an ECU. For customers who want to use a VSS or other speed sensor to provide a direct, wired speedometer connection, one of the RPM terminals can be used (please note, V3 terminals include two RPM terminals while V4 hubs only include one). Speedometer readings can be displayed in KPH or MPH as requested by the customer.
Odometer readings are included on setups and can track vehicle miles through any speedometer source (GPS, OBD-II, Can bus, or VSS). Optional included features include displaying mileage in miles or kilometers, trip meters that can be reset, and hour meters to track engine hours.
The GPS module, when purchased, provides speedometer, location, altitude, compass, and clock readings without any physical connection to the vehicle. It also provides calculated gauges such as like lap times, 1/4 mile and 1/8 mile times, 0-60 times as well. When a fuel level wire is hooked up, options for mileage and efficiency calculations are also available. The only installation required for the GPS module is the placement of the attached antenna; this magnetic antenna should either be placed on the exterior of the car or on the front of the dashboard near the windshield. The better view of the sky the antenna has, the better (and faster) your signal will be.
GPS Troubleshooting
GPS signals are relatively trouble-free, but issues occasionally arise. Please follow these steps if you are unable to get a speedometer or GPS reading.
- Check altitude reading. Many screens will have an altitude reading, which is a good way to verify if the GPS is getting a signal without having to drive the vehicle. Altitude defaults to 0 if there is no connection.
- Check the antenna. Your GPS antenna should be placed in a location with a clear view of sky. The dashboard of the vehicle under the windshield or the exterior of the vehicle, facing the sky, are the best locations. Also check the antenna wire for any damage, fraying, or cutting, which can prevent the antenna from working. If the antenna wire runs behind the dash it can get caught in moving components and damaged.
- Remove the lid from the OneGauge Hub, the black box. The GPS is located inside and is connected to the antenna (don’t confuse it with the Bluetooth module, which is close to it but has no antenna connection). When the hub is powered on, the GPS has a red or green light that will stay on. Once the GPS connects to satellites it blinks one time per second. Once the blinking begins the unit should start to receive GPS data within a few seconds. It can take 3-5 minutes for the GPS to get a satellite signal and start blinking the first time the unit is powered on, or until a signal is found if the hub isn’t left on long enough. After that though a signal is typically found within 30 seconds.
- If you have checked all of the above and the red/green light does not start blinking even after a few minutes connected to a working antenna, perform a reset on the GPS module. To do this, flash the power on/off of the OneGauge hub. Power on the OneGauge until the lights come on, then immediately power it off, then back on, and do this 5-10 times. This will reset the GPS module and often the GPS will get a connection after this.
- If the red/green light is blinking once per second but the OneGauge screen still shows 0 altitude and no speedometer readings, please reach out to OneGauge for a code update that will reprogram the GPS.
In almost all cases following these steps resolves GPS issues. If you continue to have issues let us know and we’ll replace the GPS unit on your circuit board.