Published Date: 2022-02-09
| Postmortem Analysis | |
|---|---|
| Timeline | 1. The software failure incident related to the Tesla vehicles' windshield defrosting issue occurred in December 2021 as per Article 124250. 2. The article was published on 2022-02-09. Therefore, the software failure incident happened in December 2021. |
| System | 1. Cabin heating system in some 2021-2022 Model 3, Model S, Model X, and 2020-2022 Model Y vehicles [Article 124030] 2. Heat-pump valve in Tesla vehicles causing decreased defrosting performance [Article 124250] |
| Responsible Organization | 1. Tesla [124250, 124030] 2. National Highway Traffic Safety Administration (NHTSA) [124250, 124030] |
| Impacted Organization | 1. Tesla owners of affected vehicles [Article 124250, Article 124030] 2. National Highway Traffic Safety Administration (NHTSA) [Article 124250, Article 124030] |
| Software Causes | 1. The failure incident was caused by a software error that can open a heat-pump valve unintentionally, trapping refrigerant inside the evaporator, resulting in decreased defrosting performance [124250]. 2. The error in the cabin heating system was due to a bug in the software that caused refrigerant depletion in some parts of the heat pump, leading to the compressor not working as a fail-safe measure, particularly in very cold conditions [124030]. |
| Non-software Causes | 1. The failure incident in Tesla vehicles was caused by a software error that can open a heat-pump valve unintentionally, leading to decreased defrosting performance [124250, 124030]. 2. The error may cause a valve in the heat pump to open unintentionally and trap the refrigerant inside the evaporator, affecting the windshield defrosting process [124030]. |
| Impacts | 1. Diminished visibility leading to an increased likelihood of a crash for affected Tesla vehicles due to the software error causing decreased defrosting performance [124250, 124030]. 2. Recall of 26,681 and 27,000 Tesla vehicles due to the windshield defrosting issue, affecting select cars of the company's 2021 and 2022 model-year EVs [124250, 124030]. 3. Tesla owners experiencing loss of heating performance in extreme cold weather conditions due to the software error [124250]. 4. Tesla issuing over-the-air software updates to address the defogging problem, minimizing the impact on drivers and the company [124250, 124030]. 5. The software failure incident led to Tesla not meeting federal motor vehicle safety standards until the fault is repaired, impacting the affected vehicles' compliance [124030]. 6. Increased risk of collision due to the windshield defrosting risk, prompting the recall of the affected vehicles [124030]. |
| Preventions | 1. Implementing thorough software testing procedures to catch potential bugs and errors before the software is deployed [Article 124030]. 2. Conducting more extensive quality assurance checks specifically focused on cold weather performance to identify and address any issues related to defrosting capabilities [Article 124250]. 3. Enhancing the monitoring and feedback mechanisms from customers to quickly identify and address any emerging software-related issues, such as loss of heating performance in extreme cold weather conditions [Article 124250]. 4. Implementing stricter regulations or guidelines for software updates and recalls to ensure timely and effective resolution of software-related issues [Article 124030]. 5. Enhancing communication channels between the company and customers to promptly address any reported software-related problems and provide necessary updates or fixes [Article 124250]. |
| Fixes | 1. An over-the-air software update will be performed to address the software error causing the windshield defrosting issue in the affected Tesla vehicles [124250, 124030]. 2. Vehicle owners won't need to return their cars to the showroom for the fix, as the software update can be done wirelessly [124030]. 3. Concerned owners can contact Tesla customer service at 1-877-798-3752 for more information on the software update fix [124250]. | References | 1. National Highway Traffic Safety Administration's recall website [Article 124250] 2. Tesla [Article 124030] |
| Category | Option | Rationale |
|---|---|---|
| Recurring | one_organization | (a) The software failure incident has happened again at one_organization: - Tesla has faced multiple software-related issues with its vehicles, including recalls for problems such as seatbelt warning alerts, autonomous driving system issues, and windshield defrosting risks [Article 124250]. - Tesla has issued at least nine recalls in the US since October, out of a total of 14 in the past 12 months, many of which were related to software issues [Article 124030]. (b) The software failure incident has happened again at multiple_organization: - The articles do not mention similar incidents happening at other organizations or with their products and services. |
| Phase (Design/Operation) | design, operation | (a) The software failure incident related to the design phase: - The software error causing the windshield defrosting issue in Tesla vehicles was attributed to a design flaw in the heat pump system, specifically a valve opening unintentionally and trapping refrigerant inside the evaporator, leading to decreased defrosting performance [124250, 124030]. - The issue stemmed from a software error that could open a heat-pump valve unintentionally, resulting in decreased defrosting performance, which did not meet the minimum performance requirement outlined in Federal Motor Vehicle Safety Standard rules [124250]. (b) The software failure incident related to the operation phase: - The software failure incident was exacerbated by extreme cold weather conditions, leading to a loss of heating performance reported by customers in December of 2021 [124250]. - Customers experienced issues with cabin heating not coming on in very cold weather, which was caused by a bug in the software depleting refrigerant in some parts of the heat pump, leading to the compressor not working as a fail-safe measure, particularly in very cold conditions [124030]. |
| Boundary (Internal/External) | within_system, outside_system | (a) within_system: The software failure incident related to the Tesla vehicles' windshield defrosting issue was caused by a software error within the system. The issue stemmed from a software error that could open a heat-pump valve unintentionally, leading to decreased defrosting performance [124250, 124030]. This internal software error trapped refrigerant inside the evaporator, affecting the defrosting capability of the affected vehicles [124250, 124030]. Tesla addressed this issue by planning to perform an over-the-air software update to fix the problem without requiring owners to bring their vehicles in for service [124250, 124030]. (b) outside_system: The contributing factors that originated from outside the system in this software failure incident were related to the extreme cold weather conditions that exposed the issue. Customers began to report a loss of heating performance in extreme cold weather conditions, which brought attention to the problem [124250]. The external factor of cold weather conditions highlighted the software error within the system that affected the defrosting performance of the Tesla vehicles [124250, 124030]. |
| Nature (Human/Non-human) | non-human_actions | (a) The software failure incident occurring due to non-human actions: - The software error that led to the windshield defrosting issue in Tesla vehicles was caused by a non-human action, specifically a software error that could open a heat-pump valve unintentionally, trapping refrigerant inside the evaporator and resulting in decreased defrosting performance ([124250], [124030]). (b) The software failure incident occurring due to human actions: - The article does not mention any specific human actions that directly contributed to the software failure incident. |
| Dimension (Hardware/Software) | hardware, software | (a) The software failure incident occurring due to hardware: - The software failure incident reported in the articles is related to a hardware issue where a valve in the heat pump can open unintentionally, trapping refrigerant inside the evaporator, leading to decreased defrosting performance of the windshield [124250, 124030]. (b) The software failure incident occurring due to software: - The software failure incident is primarily attributed to a software error that can open a heat-pump valve unintentionally, resulting in decreased defrosting performance of the windshield [124250, 124030]. - Tesla mentioned that they will perform an over-the-air software update to address the issue, indicating that the software itself was a contributing factor to the problem [124030]. |
| Objective (Malicious/Non-malicious) | non-malicious | (a) The articles do not mention any malicious intent behind the software failure incident. (b) The software failure incident related to the Tesla vehicles' windshield defrosting issue was non-malicious. The problem stemmed from a software error that unintentionally opened a heat-pump valve, leading to decreased defrosting performance in certain conditions [124250, 124030]. Tesla acknowledged the fault and mentioned that fixing the problem was a high priority, indicating a non-malicious nature of the failure. |
| Intent (Poor/Accidental Decisions) | poor_decisions | (a) The software failure incident related to the windshield defrosting issue in Tesla vehicles was primarily due to poor decisions. The issue stemmed from a software error that could open a heat-pump valve unintentionally, leading to decreased defrosting performance [124250, 124030]. This software error was a result of decisions made during the development and implementation of the heat pump system in the vehicles. The poor decision in the software design led to the unintended opening of the valve, trapping refrigerant and causing the windshield defrosting problem. |
| Capability (Incompetence/Accidental) | development_incompetence, accidental | (a) The software failure incident occurring due to development incompetence: - The software error that led to the windshield defrosting issue in Tesla vehicles was due to a development error where a heat-pump valve could open unintentionally, trapping refrigerant and resulting in decreased defrosting performance [124250]. - Tesla acknowledged the fault and mentioned that fixing the problem was a high priority, indicating a development error that needed attention [124250]. (b) The software failure incident occurring accidentally: - The issue with the cabin heating system failing to defrost the windshield in Tesla vehicles was described as an error that may cause a valve in the heat pump to open unintentionally, trapping refrigerant and affecting defrosting performance [124030]. - The software bug that caused refrigerant depletion in the heat pump, leading to loss of cabin heating and potential windshield defrosting issues, was not intentional but rather an accidental occurrence [124030]. |
| Duration | permanent, temporary | The software failure incident related to the windshield defrosting issue in Tesla vehicles can be considered both temporary and permanent based on the information provided in the articles. Temporary: - The issue with the windshield defrosting is temporary as it occurs under certain circumstances, specifically when temperatures drop below 14 degrees Fahrenheit [Article 124030]. - Tesla mentioned that the error may cause a valve in the heat pump to open unintentionally, trapping refrigerant inside the evaporator, which could lead to the windshield failing to defrost properly under certain conditions [Article 124030]. Permanent: - The software error causing the windshield defrosting issue is considered permanent as it is a contributing factor introduced by the circumstances of the software error that opens the heat-pump valve unintentionally [Article 124250]. - The software error can result in decreased defrosting performance, indicating a permanent issue until the software is updated to address the problem [Article 124250]. Therefore, the software failure incident can be seen as both temporary and permanent, depending on the circumstances and contributing factors involved. |
| Behaviour | omission | (a) crash: The software failure incident in the articles does not involve a crash where the system loses state and does not perform any of its intended functions. The failures mentioned are related to issues with the defrosting performance of the windshield in Tesla vehicles, which could lead to diminished visibility and potentially increase the likelihood of a crash [124250, 124030]. (b) omission: The software failure incident can be categorized under omission, as the system omits to perform its intended functions at an instance(s). Specifically, the issue stems from a software error that can open a heat-pump valve unintentionally, leading to decreased defrosting performance of the windshield [124250, 124030]. (c) timing: The software failure incident is not related to timing issues where the system performs its intended functions correctly but too late or too early. The focus of the incident is on the system's failure to defrost the windshield properly under certain circumstances [124250, 124030]. (d) value: The software failure incident does not fall under the category of value, where the system performs its intended functions incorrectly. The issue is more about the system's failure to defrost the windshield adequately due to a software error related to the heat-pump valve [124250, 124030]. (e) byzantine: The software failure incident is not characterized by a byzantine behavior, where the system behaves erroneously with inconsistent responses and interactions. The issue is more straightforward, involving a specific software error leading to decreased defrosting performance of the windshield in Tesla vehicles [124250, 124030]. (f) other: The software failure incident does not exhibit any other behavior outside of the options provided. The primary focus is on the specific software error related to the heat-pump valve that impacts the defrosting performance of the windshield in the affected Tesla vehicles [124250, 124030]. |
| Layer | Option | Rationale |
|---|---|---|
| Perception | processing_unit, embedded_software | (a) sensor: The software failure incident related to the Tesla vehicles' windshield defrosting issue was not directly attributed to a sensor error. The issue stemmed from a software error that caused a heat-pump valve to open unintentionally, leading to decreased defrosting performance [124250, 124030]. (b) actuator: The failure was not directly linked to an actuator error in the Tesla vehicles' windshield defrosting issue. The root cause was identified as a software error that resulted in decreased defrosting performance due to an open heat-pump valve [124250, 124030]. (c) processing_unit: The software failure incident in the Tesla vehicles' windshield defrosting issue was primarily attributed to a processing error. The issue originated from a software error that caused a heat-pump valve to open unintentionally, leading to diminished defrosting performance [124250, 124030]. (d) network_communication: There was no indication in the articles that the software failure incident in the Tesla vehicles' windshield defrosting issue was related to network communication errors. The issue was specifically linked to a software error affecting the heat-pump valve and defrosting performance [124250, 124030]. (e) embedded_software: The software failure incident in the Tesla vehicles' windshield defrosting issue was directly related to embedded software error. The problem was caused by a software error that unintentionally opened a heat-pump valve, resulting in decreased defrosting performance [124250, 124030]. |
| Communication | unknown | The software failure incident related to the communication layer of the cyber physical system that failed is not explicitly mentioned in the provided articles. Therefore, it is unknown whether the failure was specifically related to the link_level or connectivity_level of the cyber physical system. |
| Application | TRUE | The software failure incident related to the application layer of the cyber physical system that failed is described in the articles. The failure was due to a software error that caused a valve in the heat pump to open unintentionally, trapping refrigerant inside the evaporator and resulting in decreased defrosting performance of the windshield [124250, 124030]. This issue was specifically attributed to a bug in the software controlling the heating system of the affected Tesla vehicles, leading to diminished visibility and potential safety risks. |
| Category | Option | Rationale |
|---|---|---|
| Consequence | property, non-human, theoretical_consequence | (a) death: People lost their lives due to the software failure - There is no mention of any deaths related to the software failure incident in the provided articles [Article 124250, Article 124030]. (b) harm: People were physically harmed due to the software failure - There is no mention of any physical harm to individuals due to the software failure incident in the provided articles [Article 124250, Article 124030]. (c) basic: People's access to food or shelter was impacted because of the software failure - There is no mention of people's access to food or shelter being impacted by the software failure incident in the provided articles [Article 124250, Article 124030]. (d) property: People's material goods, money, or data was impacted due to the software failure - The software failure incident led to the recall of Tesla vehicles due to issues with windshield defrosting, potentially impacting the safety and usability of the affected vehicles [Article 124250, Article 124030]. (e) delay: People had to postpone an activity due to the software failure - There is no mention of people having to postpone activities due to the software failure incident in the provided articles [Article 124250, Article 124030]. (f) non-human: Non-human entities were impacted due to the software failure - The software failure incident affected the functionality of Tesla vehicles, specifically related to the defrosting of windshields, which is a non-human impact [Article 124250, Article 124030]. (g) no_consequence: There were no real observed consequences of the software failure - The software failure incident resulted in diminished visibility due to windshield defrosting issues in Tesla vehicles, impacting safety and potentially leading to crashes [Article 124250, Article 124030]. (h) theoretical_consequence: There were potential consequences discussed of the software failure that did not occur - The articles mention potential consequences such as decreased defrosting performance, diminished visibility, and an increased risk of collision due to the software error, but there is no mention of actual incidents of crashes, injuries, or fatalities related to the defogging problem [Article 124250, Article 124030]. (i) other: Was there consequence(s) of the software failure not described in the (a to h) options? What is the other consequence(s)? - There are no other specific consequences of the software failure incident mentioned in the articles beyond those related to vehicle safety and functionality [Article 124250, Article 124030]. |
| Domain | transportation, manufacturing, utilities | (a) The software failure incident reported in the articles is related to the transportation industry. The incident involves Tesla vehicles, specifically Model 3, Model Y, Model S, and Model X electric vehicles, experiencing a software error in the heat-pump system that affects the defrosting performance of the windshield, potentially leading to diminished visibility and an increased risk of crashes [Article 124250, Article 124030]. (g) The incident also touches upon the utilities industry, as the software error in the heat-pump system of the Tesla vehicles can trap refrigerant inside the evaporator, impacting the defrosting functionality, which is crucial for maintaining safety during transportation [Article 124250, Article 124030]. (m) Additionally, the software failure incident can be associated with the manufacturing industry, as Tesla is a manufacturer of electric vehicles, and the issue with the heat-pump system software affects the performance and safety features of the vehicles being produced [Article 124250, Article 124030]. |
Article ID: 124250
Article ID: 124030