Honda has revealed that it has discovered improper testing during the vehicle type approval application process for a number of its vehicles. The improper tests are the noise test and the power output test of its petrol and hybrid cars.
The revelation was made following the instruction by Japan’s Ministry of Land, Infrastructure, Transport, and Tourism (MLIT) on January 26, 2024, for the company to investigate if there were fraudulent acts in the vehicle type approval application.
Honda has even provided a full list of its vehicles that are affected by these improper tests but also ensures all of its customers that the affected vehicles are safe to drive with no further action needed by the customers. This is because Honda says that it has conducted technical verification and actual vehicle testing in-house and confirmed that stipulated standards are met. The tests also concern the vehicle noise level and power outputs, not the areas of safety.
Improper noise testing
What did Honda do?
This is an improper test that you could probably gloss over since it is a case of Honda exceeding what the regulation required. So the car is required to undergo a noise test and with it there is a vehicle weight requirement.
What Honda did was basically make its cars heavier than the required weight during the noise test.
Honda’s explanation
Honda’s explanation for this improper test is that “if the vehicle weight changes after testing due to design changes, etc., there is a possibility that retesting will be required. However, by conducting testing under conditions that are stricter than those stipulated by law, it was interpreted that noise performance could be guaranteed, and it was thought that an increase in the man-hours required for retesting could be avoided.”
Anyhow, Honda has listed out the cars affected by this improper test and you can view them in the table below:
| Car model | Model | Production Period | Exam Period |
| Honda Inspire | DBA-CP3 | December 2007 – July 2010 | February 2009 |
| Honda Fit | DBA-GE6,DBA-GE8,DBA-GK3,DBA-GK4, DBA-GK5,DBA-GK6,DAA-GP1,DAA-GP4, DAA-GP5,DAA-GP6 | November 2009 – September 2019 | July 2009 – February 2017 |
| Honda CR-Z | DAA-ZF1,DAA-ZF2 | February 2010 – September 2013 | September 2009 – June 2012 |
| Honda Acty | EBD-HH5, EBD-HH6, EBD-HA8, EBD-HA9 | December 2009 – September 2013 | April 2010 – January 2012 |
| Honda Vamos/ Vamos Hobio | ABA-HM1, ABA-HM2, ABA-HM3, ABA-HM4, EBD-HH5, EBD-HJ1, EBD-HJ2 | August 2010 – September 2013 | April 2010 – May 2010 |
| Stepwgn/ Stepwgn Spada | DBA-RK2, DBA-RK4, DBA-RK6, DBA-RP2, DBA-RP4 | October 2010 – August 2017 | June 2010 – October 2014 |
| Honda Legend | DBA-KB2 | October 2010 – June 2012 | June 2010 |
| Honda Accord/ Accord Tourer/ Accord Hybrid | DBA-CU1, DBA-CW1, DAA-CR6 | February 2011 – March 2016 | September 2010 – January 2013 |
| Honda Fit Shuttle | DBA-GG7, DBA-GG8, DAA-GP2 | February 2011 – July 2013 | October 2010 |
| Honda Insight Exclusive | DAA-ZE3 | November 2011 – April 2013 | January 2011 |
| Honda CR-V | DBA-RM1,DBA-RM4 | November 2011 – September 2013 | March 2011 |
| Honda Freed/Freed+/ Freed Spike | DBA-GB5, DBA-GB6, DAA-GP3, DAA-GB7 | October 2011 – September 2019 | July 2011 – May 2016 |
| Honda N-Box/ N-Box Custom | DBA-JF1,DBA-JF2 | December 2011 – January 2013 | September 2011 |
| Honda N-ONE | DBA-JG1,DBA-JG2 | October 2012 – May 2014 | June 2012 |
| Honda Odyssey | DBA-RC1,DBA-RC2 | October 2013 – September 2017 | June 2013 |
| Honda N-WGN/ N-WGN Custom | DBA-JH1,DBA-JH2 | November 2013 – May 2019 | July 2013 |
| Honda Vezel | DBA-RU2,DAA-RU3,DAA-RU4 | January 2018 – July 2020 | August 2013 – July 2017 |
| Honda Grace | DBA-GM6, DAA-GM4, DAA-GM5 | October 2014 – July 2020 | January 2014 – November 2016 |
| Honda S660 | DBA-JW5 | March 2015 – December 2019 | September 2014 |
| Honda Shuttle | DBA-GK9, DAA-GP7, DAA-GP8 | April 2015 – March 2019 | October 2014 – March 2017 |
| Honda NSX | CAA-NC1 | August 2016 – December 2019 | May 2016 |
| Honda Jade | DBA-FR5 | April 2018 – July 2020 | October 2017 |
Improper power output test
What did Honda do?
Honda altered the maximum power output and rated output figures gathered from the test and entered the altered figure into the official report. Basically falsifying data for its hybrid cars.
Honda’s explanation
The powertrains of the cars of which their data were altered were identical powertrains from other models that have been tested previously. Honda says that if the data collected from the earlier test and the newer test id not match (for the same powertrain), additional analysis would be required. Thus Honda decided to enter altered data which wouldn’t deviate too far from the initial data.
| Car model | Model | Production Period | Exam Period |
| Honda Fit | DAA-GP5,DAA-GP6 | July 2013 – September 2019 | May 2013 |
| Honda Shuttle | DAA-GP7, DAA-GP8, 6AA-GP7, 6AA-GP8 | April 2015 – August 2022 | May 2013 |
| Honda Freed/Freed+ | DAA-GB7, 6AA-GB7, DAA-GB8, 6AA-GB8 | June 2016 – May 2022 | May 2013 |
| Honda Vezel | DAA-RU3, 6AA-RU3, DAA-RU4, 6AA-RU4 | September 2013 – February 2021 | May 2013 |
| Honda Jade | DAA-FR4 | December 2014 – July 2020 | May 2013 – August 2014 |
| Honda Grace | DAA-GM4,DAA-GM5,DBA-GM6,DBA-GM9 | June 2015 – May 2017 | May 2013 – March 2015 |
| Honda Odyssey | DBA-RC1,6BA-RC1 | October 2013 – September 2020 | September 2014 |
| Honda NSX | CAA-NC1, 5CA-NC1 | July 2016 – October 2022 | June 2015 |
Correction value used in power output test
What did Honda do?
Provide an output test result without actually running the powertrain. Since the regulation didn’t explicitly require it for the specific model, Honda reused data from another vehicle that had the same powertrain, albeit with some correctional inputs for the new car.
Honda’s explanation
The regulation did not state that an actual test with the engine running was required. Hence Honda used correction values (with reference to older tests) to reduce its man hours. Honda the correction values to be the same as the test results. However, this is considered a deficiency in test conditions.
Vehicles affected by the improper power output test (correction value):
| Car model | Model | Production Period | Exam Period |
| Honda Fit | DBA-GK3,DBA-GK4 | July 2013 – September 2020 | April 2013 |
| Honda Shuttle | DBA-GK8,DBA-GK9 | April 2015 – August 2017 | September 2014 |
| Honda Odyssey | DBA-RC1, DBA-RC2, 6BA-RC1, 6BA-RC2 | October 2013 – September 2020 | September 2014 |
| Honda Jade | DBA-FR5 | May 2015 – July 2020 | January 2015 |
So that’s the improper testing by Honda for you. It doesn’t concern safety, but Honda takes this very seriously and will work to prevent this from recurring. And as said earlier, Honda ensures its customers that no further action is required by the them as the vehicles are safe to be driven.
