Incident: Faulty Shift Lever Micro Switch Causes Volkswagen Recall.

Published Date: 2019-08-23

Postmortem Analysis
Timeline 1. The software failure incident of the Volkswagen recall happened when the fault in the shift lever was detailed in documents published with NHTSA on Thursday [88248]. 2. Published on 2019-08-23. 3. The incident likely occurred around August 2019.
System 1. Shift lever micro switch in affected Volkswagen models [Article 88248]
Responsible Organization 1. The software failure incident in the Volkswagen recall was caused by a fault in the shift lever micro switch, leading to a rollaway risk [88248].
Impacted Organization 1. Volkswagen [88248]
Software Causes 1. Silicate buildup on the shift lever micro switch causing it to identify a false positive, leading to the vehicle not being in Park when the key is removed [88248].
Non-software Causes 1. Buildup of silicate on the shift lever micro switch [88248] 2. Failure of the actual micro switch [88248]
Impacts 1. The software failure incident in Volkswagen cars led to a rollaway risk, increasing the possibility of crashes and injuries [88248].
Preventions 1. Implementing rigorous testing procedures during the development phase to detect and address potential issues with the shift lever micro switch [88248]. 2. Regularly monitoring and analyzing data from the vehicles in the field to proactively identify any emerging faults or anomalies related to the shift lever system [88248]. 3. Conducting thorough risk assessments and safety evaluations on critical components like the shift lever micro switch to ensure early detection of any potential safety risks [88248].
Fixes 1. Volkswagen plans to disable the micro switch already present at the gear lever and install an additional switch outside of the gear lever housing along with another circuit board to ensure proper procedure [88248].
References 1. NHTSA documents [88248]

Software Taxonomy of Faults

Category Option Rationale
Recurring unknown (a) The software failure incident related to the faulty shift lever in Volkswagen cars does not mention any previous similar incident happening within the same organization. (b) The software failure incident related to the faulty shift lever in Volkswagen cars does not mention any similar incident happening at other organizations or with their products and services.
Phase (Design/Operation) design, operation (a) The software failure incident in the Volkswagen recall is related to the design phase. The fault in the shift lever that poses a rollaway risk was caused by silicate buildup on the shift lever micro switch, which led to the components identifying this buildup as an open micro switch, incorrectly denoting the vehicle as being in Park. This design flaw allowed drivers to remove the key from the ignition without the vehicle actually being in Park, increasing the risk of rollaway incidents and potential crashes [88248]. (b) The software failure incident in the Volkswagen recall is also related to the operation phase. Volkswagen mentioned that some models may produce warning sounds or error messages while driving, which would signal that the actual micro switch has failed. This indicates that the operation of the system, specifically the detection and signaling of the micro switch failure during driving, contributed to identifying the issue [88248].
Boundary (Internal/External) within_system (a) within_system: The software failure incident described in the article is related to a fault in the shift lever of the affected Volkswagen vehicles. The issue is specifically with the shift lever micro switch, where silicate buildup can cause the components to identify a false positive, indicating the vehicle is in Park when it may not be. This internal system fault leads to a rollaway risk, increasing the possibility of a crash and injury [88248]. (b) outside_system: There is no information in the article indicating that the software failure incident was caused by contributing factors originating from outside the system.
Nature (Human/Non-human) non-human_actions, human_actions (a) The software failure incident in the Volkswagen recall was primarily due to non-human actions. The fault in the shift lever was caused by silicate buildup on the shift lever micro switch, which led to the components identifying a false positive of the vehicle being in Park when it was not. This non-human factor introduced a risk of rollaway for the affected vehicles [88248]. (b) Human actions were involved in addressing the software failure incident. Volkswagen announced a fix where technicians will disable the existing micro switch and install an additional switch outside of the gear lever housing along with another circuit board to rectify the issue. Additionally, VW will offer a reimbursement program for owners who fixed the problem and paid out of pocket, indicating human intervention in resolving the software failure [88248].
Dimension (Hardware/Software) hardware (a) The software failure incident in the Volkswagen recall is related to hardware. The fault in the shift lever that poses a rollaway risk is caused by silicate buildup on the shift lever micro switch, which is a hardware component. Volkswagen plans to disable the existing micro switch and install an additional switch outside of the gear lever housing, along with another circuit board, to address the issue [88248].
Objective (Malicious/Non-malicious) non-malicious (a) The software failure incident described in the article is non-malicious. The fault in the shift lever that poses a rollaway risk in Volkswagen cars is attributed to the buildup of silicate on the shift lever micro switch. This buildup causes the components to identify a false positive, leading to the incorrect indication that the vehicle is in Park when it is not, potentially resulting in a rollaway risk [88248].
Intent (Poor/Accidental Decisions) unknown The software failure incident described in Article 88248 does not directly point to either poor_decisions or accidental_decisions as the intent behind the failure. The issue with the shift lever micro switch buildup of silicate leading to a rollaway risk seems more related to a technical fault rather than poor or accidental decisions.
Capability (Incompetence/Accidental) accidental (a) The software failure incident in the Volkswagen recall is not directly attributed to development incompetence. The issue described in the article is related to a fault in the shift lever that poses a rollaway risk due to silicate build-up on the shift lever micro switch, leading to a false positive identification of the vehicle being in Park. This issue is more related to a design or manufacturing flaw rather than development incompetence [88248]. (b) The software failure incident in the Volkswagen recall is more aligned with an accidental failure. The fault in the shift lever that poses a rollaway risk was not intentional but rather a result of silicate build-up on the shift lever micro switch, causing a false positive identification of the vehicle being in Park. This unintended consequence led to the potential risk of the affected vehicles rolling away, increasing the possibility of a crash and injury [88248].
Duration temporary The software failure incident described in the article is more aligned with a temporary failure rather than a permanent one. The issue with the shift lever micro switch in the affected Volkswagen vehicles is caused by the buildup of silicate on the switch, leading it to incorrectly identify the gear position. This issue is not inherent to the design of the vehicles but rather a result of the specific circumstance of silicate buildup affecting the switch functionality. As a temporary fix, Volkswagen plans to disable the existing micro switch and install an additional switch outside of the gear lever housing, indicating that the issue can be rectified by addressing the specific contributing factor of silicate buildup [88248].
Behaviour value (a) crash: The software failure incident in the Volkswagen recall is not described as a crash where the system loses state and does not perform any of its intended functions [88248]. (b) omission: The software failure incident in the Volkswagen recall is not described as an omission where the system omits to perform its intended functions at an instance(s) [88248]. (c) timing: The software failure incident in the Volkswagen recall is not described as a timing issue where the system performs its intended functions correctly, but too late or too early [88248]. (d) value: The software failure incident in the Volkswagen recall is related to a value issue where the system performs its intended functions incorrectly. Silicate buildup on the shift lever micro switch causes the components to identify a false positive, indicating the vehicle is in Park when it is not, leading to a rollaway risk [88248]. (e) byzantine: The software failure incident in the Volkswagen recall is not described as a byzantine failure where the system behaves erroneously with inconsistent responses and interactions [88248]. (f) other: The software failure incident in the Volkswagen recall is not described as any other specific behavior not covered by the options provided [88248].

IoT System Layer

Layer Option Rationale
Perception None None
Communication None None
Application None None

Other Details

Category Option Rationale
Consequence harm, theoretical_consequence The consequence of the software failure incident described in the article is related to potential harm to individuals due to the fault in the shift lever. The article mentions that the fault in the shift lever poses a rollaway risk, which could lead to a possibility of a crash and injury [88248].
Domain transportation The software failure incident reported in Article 88248 is related to the transportation industry. Volkswagen is set to recall a significant number of cars due to a fault in the shift lever that poses a rollaway risk [88248]. The affected vehicles include various models equipped with automatic transmissions, a manual handbrake, and keyless entry, which are essential components in the transportation sector. The fault in the shift lever's micro switch could lead to a situation where drivers can remove the key from the ignition without the vehicle actually being in Park, increasing the risk of rollaway incidents, crashes, and injuries, all of which are critical concerns in the transportation industry. The recall and the fix proposed by Volkswagen are directly related to ensuring the safety and proper functioning of vehicles in the transportation sector.

Sources

Back to List