MyGreenVolt

Wiki

Bluetooth adapter

Every recent car comes with a diagnostic port located on the driver side. In order for the application running on your smartphone to get data through this port, an OBD2 Bluetooth (or WiFi) adapter needs to be used. Those adapters can be found online and their price range from $15 to $100. The more expensive versions include better power management, high reliability and will go to low power mode once the application is disconnected.

If you plan to use you adapter on a daily basis which is recommended to keep track of your statistics, I would advise to use an OBDLink LX or any other good reputation brand.

Once you get your adapter, plug it in and use the bluetooth setting of your device to pair it. If you skip this step, you won't see the device in the app.

Note: The built-in bluetooth of the car is used for audio purposes and should not be paired with MyGreenVolt app.

 

First connection

When the application is started for the first time (or after an update), you will be presented with the agreement. Once accepted, you are redirected to the connection tab showing all the paired devices you can connect to. Make sure you select the righ bluetooth device. Usually, they include the OBD acronym. Once the connection is established, the app switches to the main Dashboard. For any subsequent execution of the app, you do not need to select your device anymore as it was stored in the app preferences. If you want to selct your device each time you start the app, unselect "Reconnect to last device" in the settings section.

Dashboard

The Dashboard tab is the main screen presenting the various metrics the app reads from the vehicule. The screen is divided in 6 sections described below.

Power and efficiency

The top left section gather information related to power and efficiency.

 

The first line shows both the minimum and maximum power at the battery level (main traction battery).

The second line also displays two numbers. The left one is the instant power in kiloWatts (kW). The right number is your instant efficiency (in mile per kiloWatt hour or kilometer per kiloWatt hour). This is equivalent to the mpg of a gas car. The higher this number, the better the efficiency and range. If the power number turns red, it means that your friction brakes are applied.

Finally, the last row is the amps and voltage of the traction battery. Negative amps means current is flowing back to the battery (regen).

Power graph

The Volt includes two electic motors. The instant power of both motors is shown for roughly the past ten seconds.

Temperature

The temperature of different sub-systems is represented on this bar graph.

The first bar is the average battery temperature. It can be either green or red. When red, the battery heater is on and warms up the battery.

The transmission is the second horizontal bar. This is the coupling between the different motors (gas and electric) and the drive train. 

The electronics temperature includes the AC to DC charger and the DC to AC converter generating the AC power from the battery.

The last bar is the gas engine coolant temperature.

Energy breakdown

The pie chart provides an estimated break down of the energy consumption. The green section is the energy used for propulsion i.e from the electric motors. The red portion is the energy used from the cabin heater.

The orange represents the energy of the battery heater.

Yellow is used to run the onboard electronics, head lights, etc. This is typical the idle power consumption when the car is not moving (around 400W).

Energy

This is a busy screen with many metrics showing average values which are not updated as fast as the  first screen for instance.

The first number is the average efficiency. As for the first screen, it shows your efficiency in mile per kwh or kilometers per kWh.

The second number is also a way to estimate the efficiency but the unit is the opposite of the previous one as in kWh per mile (or km).

The third number is your energy consumption in kWh. This is equivalent (but not necessary equal) to the number shown on the Driver Information Center of the car (midle screen). This is the net energy including outgoing and incoming.

The forth number is the energy only coming back to the battery which can been seen as the energy recovered or regenerated during decelaration phases for instance.

The green car only moves when data is received from the car and its speed is proportionel to the bluetooth data rate.

Selectable PIDs/Data

You can select up to five metrics on the last sector (bottom right). The selection can be done in the settings tab selecting "PIDs to display". The following data is available:

- RPM: show the gas engine RPM

- SPEED: show the vehicle speed either using the data from the car or from the GPS(selectable in the settings "Use GPS speed")

- EV_KM: electric mileage only

- ELECTRIC_EFFICIENCY: efficiency in Wh/ml (or km)

- CONNECTION_TIME: Time the connection is done with the car/BT adapter. It auto resets once the car is disconnected more than couple of minutes.

- CLUTCH_SLIP: there are 3 clutches in the car to engage/disengage different motors. You could check some videos on youtube explaining what do C1/C2/C3 mean.

- COOL_PUMP_RPM: Colling pump RPM. This is a good indicator to check if the cooling pump used for battery  and/or cabin cooling is running.

- FUEL_EFFICIENCY: in mile per galon or liter per 100km. This is different from what the car shows as this number is calculated only when the gas engine is running. It does not take into account electric energy generated back to the battery by the gas engine.

- TIMING_ADVANCE: ignition timing advance (gas engine)

- BATTERY_CELL_VOLTAGE: The Volt from 2011 to 2015 has 288 element. Three element are connected in parallel to make a group. There are 96 groups connected in series. This metric show the minimum, maximim and average group voltage.

 

Configuration

A Settings tab in the app is used to set units, car model year, etc.

 

In addition, starting from release 1.0.5, a setting file can be used to override some default parameters as the audio file used when friction brakes engaged or adding an offset to the lifetime data (displayed at the bottom of the statistics tab).

The first step to overide the default parameters is to rename the following file <Internal Storage>/MyGreenVolt/settingsExample.json.txt to settings.json (same folder). Make sure to remove the txt extension. Then use a text editor to edit the file. If the editor cannot recognize the file type, just leave the txt extension and remoce it once your edits are done.

The format of the file is described below.  Each settings is defined as a key pair (e.g. "FrictionBrakeSound": "carbraking.mp3"). The first value of the key is the name of the setting and the second one the value. The line below the key pair starting with "_comment" is the description of the setting.    

 

The first parameter is FrictionBrakeSound and is used to provide the name of the audio file played when friction brake is detected (make sure the "play sound" is selected in the Settings tab of the app). The file must be in the MyGreenVolt/sounds directory. Both mp3 and wav format not exceeding 100kB are supported. Just name the file without the path.

 

The next parameter is FrictionBrakeSpeed which set the lower bound to play the sound. If the vehicule speed is lower than this value, no sound will be played. The purpose is prevent playing a sound each time you make a stop. The unit is in km per hour.

 

All the following parameters are used to add an offset to the lifetime data shown at the end of the statistics tab.

               
{

"FrictionBrakeSound": "carbraking.mp3",
"_comment":"FrictionBrakeSound sets the mp3 sound file used to play a sound when friction brakes engage.",

 

"FrictionBrakeSpeed": 10,
"_comment":"FrictionBrakeSpeed sets the speed below which the sound is played when friction brakes engaged. Unit in km/h",

 

"LifetimeMileageOffset": 0,
"_comment":"LifetimeMileageOffset is added to the lifetime mileage number shown at the bottom of the statistics tab",

 

"LifetimeFuelOffset": 0,
"_comment":"LifetimeFuelOffset is added to fuel volume in Statistics tab",

 

"LifetimeEnergyOffset": 0,
"_comment":"LifetimeEnergyOffset is added to total Energy in the Statistics tab",

 

"LifetimeElectricMileageOffset": 0,
"_comment":"LifetimeElectricMileageOffset is added to the value shown in the statistics tab"
}