Fountain Valley, Calif. – May 1, 2018 – Hyundai Motor America has recalled more than 580,000 vehicles potentially equipped with defective air bag and seat belt assemblies, according to documentation submitted to the National Highway Transportation Safety Administration. The campaign affects 2011-2013 Hyundai Sonata sedans produced between Dec. 11, 2009, and Aug. 31, 2012, along with 2011-2012 Hyundai Sonata Hybrid sedans produced between Dec. 2, 2010, and Aug. 23, 2012. The South Korean automaker suspects all of the vehicles referenced in the recall contain the defective parts.
The Defect
Affected models contain air bag control units powered by application-specific integrated circuits. These components are designed to trigger advanced air bag systems and seatbelt pretensioners in the event of an accident. However, the ACUs installed in the recalled vehicles feature ASICs that lack circuit-protecting diodes. Without these electrical parts, the ASICs may experience overstress and eventually fail, inhibiting ACU functionality and leaving occupants without crash protection. Consequently, this defect poses a serious hazard to owners. Hyundai has received at least five reports linking the defective part to accidents and injuries.
Timeline of Events
The automaker in February 2012 received a report outlining an instance in which the AAS in a 2011 Hyundai Sonata seemed to fail during an accident, according to an internal chronology document submitted to the NHTSA. Hyundai engineers inspected the vehicle referenced in the report in June 2012 and found that the vehicle had not recorded a crash event. The car company then reached out to the Michigan-based supplier ZF TRW, which had provided the ACU components installed in the vehicle. The vendor discovered signs of electrical overstress within the ACU’s ASIC assembly, a condition it linked to a number of aftermarket accessories that were installed on the model referenced in the report.
Hyundai in May 2015 received a report detailing another instance of AAS non-deployment. In October 2015, engineering teams inspected the vehicle, a 2011 Hyundai Sonata, and determined that the ACU was not functioning. ZF TRW reviewed the component and again found signs of electrical overstress. The vehicle did not contain aftermarket parts, indicating that the condition may not be linked to the installation of such non-standard components. As a result, Hyundai initiated a field review.
The automaker received two additional reports centered on AAS non-deployment between July and November 2016. While one was invalidated by investigators, the second involved a 2011 Hyundai Sonata sedan with potential ASIC damage linked to overstress. Hyundai launched an official investigation in response. Then, in November 2017, OSHA’s Office of Defects Investigation contacted the car company to check on the status of the inquiry. Hyundai submitted data related to the investigation and established a communication channel for updates. One month later, the automaker hired an external engineering firm to look into the ACU issue.
On February 21, 2018, Hyundai and ZF TRW met to discuss the state of the ongoing investigation, with the latter coming to the conclusion that transient charges, originating from adjacent vehicle parts, were causing electrical overstress in the ASIC assemblies and therefore affecting ACU performance. One day later, members of Hyundai’s Technical Committee convened and determined that a voluntary recall involving affected 2011 Hyundai Sonata sedans was necessary. Following this action, the automaker continued its investigation into the problematic ACU components.
ODI officials and Hyundai met in Washington D.C. March 9, 2018, to discuss the inquiry and the initial findings from the third-party engineering firm. It was during this meeting that Hyundai revealed that its external collaborator had determined that the ACU failure was the result of equipment failure – specifically a lack of circuit-protecting diodes. The automaker attested to replicating the equipment-related damage in a series of crash tests. This discovery expanded the pool of potentially affected models to include Hyundai Sonata and Sonata Hybrid sedans produced in 2012 and 2013. On April 3, 2018, the two parties met once more to review the ongoing investigation.
Between April 11, 2018, and April 12, 2018, Hyundai collaborated with ZF TRW to review the ACU damage sustained in the previously conducted crash tests. Both automaker and vendor agreed hat the ASIC assemblies in these components shorted due to lack of diodes. On April 18, 2018, the Hyundai TC decided to expand the existing recall, an action the group communicated to both dealers and owners April 20, 2018.
The Solution
Hyundai has not yet developed a viable remedy, according to an NHTSA recall acknowledgment document. Owners in need of assistance can contact Hyundai customer service personnel by calling (855) -371-9460. Callers should use the internal recall identification number 174. Owners can also reach out to the NHTSA directly using the agency’s Vehicle Safety Hotline at (888) 327-4236.
