Brake Test - SAE J2909 Brake Force

Updated on Mar 4, 2026

The SAE J2909 Brake Force plugin for VBOX Test Suite gives you the ability to complete a series of Brake stops that conform to the SAE J2909 specification.

Using a Brake pedal force sensor, the software will automatically start the test at the required 60 N of pressure as well as check application rates and all pass criteria as stated in J2909 document. Once the test has been completed, the software will compile the results, correct for temperature and surface conditions before producing the required ‘Tanh’ Curve fit to the results and a ‘13th stop’ value.

The SAE J2909 Brake Force plugin has a unique Test Setup ribbon, from which you can configure the test.

VBTS_J2909_TestSetup

Image missing

Click on the Configure button to open the Settings window where you can define the parameters of the test.

Click on the Report button to create a report from the current test results.

Click on the Maths Channels button to open the Maths Channels window to configure unique maths channels. You can find more information about maths channels in the Test Setup section.

Click on the Save Settings button to save the current test setup and add it to the Saved Settings area in the Add Test window.

The test will also be added to the list under the Brake button on the Home tab for easy access.

Click on the Export button to display a dropdown menu with the export options. You can export the selected results or line results to a .csv or a .txt file. 

VBTS_J2909_TestSetup_Gate

Image missing

Click on the Add Gate button to add a virtual gate to the chart and map at the point of the cursor. Gates are indicated by green lines. The currently selected gate will be indicated by a blue line.

You can now use the gates to define start and/or end conditions.


Image missing

Click on the Add Gate button to add a virtual gate to the chart and map at the point of the cursor. Gates are indicated by green lines. The currently selected gate will be indicated by a blue line.

You can now use the gates to define start and/or end conditions.

When you have added a gate, the name of the currently selected gate will be displayed in the name box. Click on the arrow in the box to see a dropdown list of all the added gates. The gates will be named according to the type of gate (if applicable) and the order it was added.  

Note: You cannot have multiple gates with the same name.

When you have added a gate, you can specify the gate width. The default gate width is 20 m.

Type the required width in the Width (m) value box. 

Click on the Rename button to edit the currently selected gate line.

Click on the Delete button to delete the currently selected gate line. 

Click on the Delete All button to delete all set gates for the session. 

Click on the Export button to export the created gate(s) as an .spl file. This file can be reused at a later date and with another VBOX product.

Click on the Import button to import a previously saved or provided .spl file. When the file is imported, the gates will be added in the order that they were saved in the .spl file.


Image missing

The Add button adds a column to the Test Results area. Click this button to open a dropdown menu where you can select a channel to display in the test results window.

When you select a column header in the Test Results area, the channel name will be displayed in the Channel box (the top box in the Data Column section). Some columns will have required channels and cannot be changed, but if you can change the channel, the Channel box will become a drop-down list with the available channels.    

Data column_SelectedColumn_DefaultChannel
Data column_SelectedColumn_EditChannel
Data column_SelectedColumn_DefaultChannel
Data column_SelectedColumn_EditChannel

When you select a column header in the Test Results area, and it is a changeable channel, the Condition dropdown menu becomes available. The conditions will depend on the test and selected channel.

Examples are:

  • Avg
  • Max
  • Min
  • Delta 
  • At Start
  • At End

The Sort Ascending button will sort the values in the currently selected column in the Test Results area in alphabetical order from A to Z.

The Sort Descending button will sort the values in the currently selected column in the Test Results area in alphabetical order from Z to A.


Image missing

Click on the Select All button to select every run in the Test Results area with one click.

Run -  Deselect All 

Click on the Deselect All button to deselect every run in the Test Results area with one click.

Click on the Deselect All button to deselect every run in the Test Results area with one click.


Image missing

Click on the Edit Data button to open the Session Data window and add various vehicle and test information, such as:

VBTS_J2909_SessionData

Vehicle

  • Vehicle Model
  • Vehicle Number
  • Vehicle Weight (kg)
  • Driver Name
  • Transmission
  • Engine Size
  • Power

Brakes

  • Front
    • Brake
    • Disc/Drum
    • Pads
  • Rear
    • Brake
    • Disc/Drum
    • Pads
  • ABS/ESC
    • Manufacturer
    • Model
    • Hardware/Software

Wheels/Tyres

  • Front
    • Wheel
      • Material
      • Dimensions
    • Tyres
      • Make 
      • Dimensions
      • Model
      • Pressure (psi)
      • Left Serial No
      • Left Batch No
      • Right Serial No
      • Right Batch No
  • Rear
    • Wheel
      • Material
      • Dimensions
    • Tyres
      • Make 
      • Dimensions
      • Model
      • Pressure (psi)
      • Left Serial No
      • Left Batch No
      • Right Serial No
      • Right Batch No

Test

  • Test Date
  • Test Number
  • Test Track
  • Test Facility
  • Test Requestor
  • Comments

Conditions

  • Road Type
  • PFC act
  • PFC spec
  • Weather
  • Track Temperature at start (ºC)
  • Track Temperature at end (ºC)
  • Ambient Temperature (ºC)
  • Humidity % 
  • Wind Speed (km/h)

When in Offline mode, the Session Data will be saved into the VBOX file.  This information will be recalled every time the file is loaded into VBOX Test Suite.

When in Online mode, a newly created session will be populated with session data from the previous session.

To save time, you can import and export the session data for other sessions. When you have completed the Session Data, you can export the data to a .vbses file by clicking on the Export button in the Session Data window. The exported file will contain all the session data and can be imported into another session via the Import button in the Session Data window.


Image missing

Click on Help to automatically open an Internet browser and load the relevant section of the User Guide on the Racelogic Support Centre.

If you are creating a new test, the Settings window will open when you add the new test. This is where you can define the test parameters.

If you have already added an Accel test and you have it open, you can click on the Configure button to open the Settings window to define or amend the test parameters.

VBTS_J2909_Settings

This setting defines when the test will start.

Click on the dropdown arrow to see the list of available channels and select either a Brake Pedal Force channel (for when 60 N has been passed) or a trigger that will start the test .
 

Target Speed (km/h)

The Target Speed is used as pass condition. Any test that is started more than 3 km/h away from the specified speed will be highlighted as a Failed run.
 

Minimum Trigger Speed (km/h)

To eliminate any false triggers (i.e, slowing for a turnaround), you can enter a Minimum Trigger Speed, to stop applications of the brake below the set speed from starting a test run.
 

Zero Brake Force Channel?

Tick this option to automatically zero the brake force sensor.

As all sensors have bias and offsets, ticking this option will make the software take an average pedal force value when the vehicle is accelerating and then apply this value to all subsequent readings.

VBTS_J2909_Settings_TestCondition

This setting defines when the test will start.

Click on the dropdown arrow to see the list of available channels and select either a Brake Pedal Force channel (for when 60 N has been passed) or a trigger that will start the test .
 

Target Speed (km/h)

The Target Speed is used as pass condition. Any test that is started more than 3 km/h away from the specified speed will be highlighted as a Failed run.
 

Minimum Trigger Speed (km/h)

To eliminate any false triggers (i.e, slowing for a turnaround), you can enter a Minimum Trigger Speed, to stop applications of the brake below the set speed from starting a test run.
 

Zero Brake Force Channel?

Tick this option to automatically zero the brake force sensor.

As all sensors have bias and offsets, ticking this option will make the software take an average pedal force value when the vehicle is accelerating and then apply this value to all subsequent readings.

VBTS_J2909_Settings_TestCondition

This area is an optional extra where you can select which channels relate to the brake temperature channels. This will then be used to identify when the brake temperatures are out of the 80 to 120 ⁰C region specified in the J2909 document. Runs outside of this region will be highlighted as a Failed run.
 

Front Left

Click on the dropdown arrow to see the list of available channels and select the brake temperature input for the front left wheel. 
 

Front Right

Click on the dropdown arrow to see the list of available channels and select the brake temperature input for the front left right. 
 

Rear Left

Click on the dropdown arrow to see the list of available channels and select the brake temperature input for the rear left wheel. 
 

Rear Right

Click on the dropdown arrow to see the list of available channels and select the brake temperature input for the front right wheel. 

VBTS_J2909_Settings_BrakeTemperature

This area is an optional extra where you can select which channels relate to the brake temperature channels. This will then be used to identify when the brake temperatures are out of the 80 to 120 ⁰C region specified in the J2909 document. Runs outside of this region will be highlighted as a Failed run.
 

Front Left

Click on the dropdown arrow to see the list of available channels and select the brake temperature input for the front left wheel. 
 

Front Right

Click on the dropdown arrow to see the list of available channels and select the brake temperature input for the front left right. 
 

Rear Left

Click on the dropdown arrow to see the list of available channels and select the brake temperature input for the rear left wheel. 
 

Rear Right

Click on the dropdown arrow to see the list of available channels and select the brake temperature input for the front right wheel. 

VBTS_J2909_Settings_BrakeTemperature

You can specify a channel that can be used to easily identify if certain parameters have exceeded a set threshold. Any runs that have exceeded the specified values will be highlighted red to mark it as Failed

The pass conditions can be set so that the run fails whenever the threshold is exceeded, either at the start of the test, at the end of the test, anytime during the test or averaged during the test.
 

Channel 

Click on the dropdown arrow to see the list of available channels and select the one required for the condition. 
 

Min Value

Specify the minimum value for the condition. 

Use the arrow buttons next to the value box to increase/decrease the value or type the required value directly into the value box. 
 

Max Value

Specify the maximum value for the condition. 

Use the arrow buttons next to the value box to increase/decrease the value or type the required value directly into the value box. 
 

At

Click on the dropdown arrow to select the required time for the condition.

  • Anytime
  • Average 
  • Start of Test
  • End of Test
  • Gate X
     
Add

Click on the + button to add another condition.
 

Delete

Click on the button to remove a condition.

VBTS_J2909_Settings_PassConditions

You can specify a channel that can be used to easily identify if certain parameters have exceeded a set threshold. Any runs that have exceeded the specified values will be highlighted red to mark it as Failed

The pass conditions can be set so that the run fails whenever the threshold is exceeded, either at the start of the test, at the end of the test, anytime during the test or averaged during the test.
 

Channel 

Click on the dropdown arrow to see the list of available channels and select the one required for the condition. 
 

Min Value

Specify the minimum value for the condition. 

Use the arrow buttons next to the value box to increase/decrease the value or type the required value directly into the value box. 
 

Max Value

Specify the maximum value for the condition. 

Use the arrow buttons next to the value box to increase/decrease the value or type the required value directly into the value box. 
 

At

Click on the dropdown arrow to select the required time for the condition.

  • Anytime
  • Average 
  • Start of Test
  • End of Test
  • Gate X
     
Add

Click on the + button to add another condition.
 

Delete

Click on the button to remove a condition.

VBTS_J2909_Settings_PassConditions
Display In
  • Select Columns to display each interim result as a column on the right-hand side of the results table. 
  • Select Separate Table to display each interim result as a row in a separate table next to the results table.
     
Conditions

You can display intermediary results that are determined by any added Interim Conditions.

Click the + button to add a new interim result condition.

Every: The Interim Result will be displayed Every time VBOX Test Suite records the set value (e.g. every 10 km/h), 

At: The Interim Result will be displayed At an instance of a value (e.g. only at 10 km/h).

Between: The Interim Result will be displayed when between values (e.g. between 30 km/h and 50 km/h). 

Select the source channel of the Interim Result and specify the required value. 

You can delete a condition by clicking on the button to the right of the relevant condition.

VBTS_J2909_Settings_InterimResults
Display In
  • Select Columns to display each interim result as a column on the right-hand side of the results table. 
  • Select Separate Table to display each interim result as a row in a separate table next to the results table.
     
Conditions

You can display intermediary results that are determined by any added Interim Conditions.

Click the + button to add a new interim result condition.

Every: The Interim Result will be displayed Every time VBOX Test Suite records the set value (e.g. every 10 km/h), 

At: The Interim Result will be displayed At an instance of a value (e.g. only at 10 km/h).

Between: The Interim Result will be displayed when between values (e.g. between 30 km/h and 50 km/h). 

Select the source channel of the Interim Result and specify the required value. 

You can delete a condition by clicking on the button to the right of the relevant condition.

VBTS_J2909_Settings_InterimResults

You can rename a session tab by double-clicking the tab header. Changing the name on the session tab in the software will automatically change the name of the locally saved VBOX file (.vbo or .vbb).

By pressing the Edit Data button next to the name of the session in the Test Results area or on the Test Setup tab on the ribbon, you can add vehicle and test information to the session.

  • When in Offline mode, this information will be saved into the VBOX file, meaning that this information will be recalled every time the file is loaded into VBOX Test Suite.
  • When in Online mode, a newly created session will be populated with session data from the previous session.

This information will be included in the test report to make it easier to see under what conditions the test was conducted.

To save time, you can import and export the session information for use in other sessions (the entire range of data is exported, not just the visible screen).

Once the session information has been completed, you can export the data to a .vbses file. This file will contain all the session information that can then be imported into the open session information field.

VBTS_J2909_Results

The Test Results area has the following default columns:

Run
Indicates which run number the results relate to, with run one being the first run completed.

There is also a selection box that, when ticked, includes the run in the graph and in the Average/Max/Min/Standard Deviation calculations. Once selected, a colour will appear to indicate which colour this run is displayed as on the graph.
 
Note: If you are loading a file in Offline mode, all valid runs will automatically be ticked.
Start Speed (km/h)
The speed at which the test started.
Time (s)
The total time the run has taken.
Uncorrected Distance (m)
The total distance travelled from start of test to the end of test.
Speed Corrected Distance (m)
The distance travelled from start of test to end of test, taking into account the stopping distance, target speed and start speed as per the J2909 regulations.
Brake Force @ 0.2s (N)

The brake force measured 0.2 seconds after the test had started.

Note: This result is not displayed if you have selected Trigger as the start of test.
Brake Rate

A Pass/Fail indication as to whether the brake pedal was applied at a rate >6000 N/s 0.1 seconds after reaching 20 N (anytime between 20 N and 0.1 seconds later).

Note: This result is not displayed if you have selected Trigger as the start of test.

The software will automatically add columns based on the configured settings.