Incident: Weak Retention Force in Wiring Harness Connectors Causes Mazda Recall

Published Date: 2019-07-02

Postmortem Analysis
Timeline 1. The software failure incident involving Mazda's 2018 CX-9 crossover occurred between September 12, 2017, and November 9, 2017 [87005]. Therefore, the software failure incident happened in September to November 2017.
System The software failure incident mentioned in the article is related to a wiring harness issue in the 2018 Mazda CX-9 crossover vehicles. Specifically, the failure occurred in the wiring harness connectors that caused disruptions between different control modules in the car. The affected components/systems/models are: 1. Wiring harness connectors in the 2018 Mazda CX-9 crossover [87005].
Responsible Organization 1. Weak retention force in some wiring harness connector terminals caused disruptions between different control modules in the car, leading to the software failure incident in Mazda vehicles [87005].
Impacted Organization 1. Mazda [87005]
Software Causes 1. Weak retention force in wiring harness connector terminals causing disruptions between different control modules in the car, leading to various issues like turn signals not working, engine not restarting, and passenger-side front airbag not deploying [Article 87005].
Non-software Causes 1. Weak retention force in wiring harness connector terminals causing disruptions between control modules in the car [87005].
Impacts 1. Turn signals may stop working. 2. The engine might not restart. 3. The passenger-side front airbag may not deploy in a crash. [87005]
Preventions 1. Implementing thorough quality control checks during the manufacturing process to ensure proper wiring harness assembly and connector terminal retention [87005]. 2. Conducting comprehensive testing and validation of the vehicle's electrical system to detect any weak retention forces or disruptions between control modules before the vehicles are released to the market [87005]. 3. Regularly monitoring and analyzing feedback from customers and conducting proactive inspections to identify potential issues with the wiring harness connectors before they lead to safety hazards [87005].
Fixes 1. Installing new harness connector terminals or replacing parts of the harness [87005]
References 1. Mazda - The information about the software failure incident is gathered directly from Mazda as they announced the recall and provided details about the issue [87005].

Software Taxonomy of Faults

Category Option Rationale
Recurring unknown (a) The article does not mention any previous incidents of a similar nature happening again within the same organization (Mazda) or with its products and services. Therefore, there is no information available to indicate a recurrence of the software failure incident within Mazda. (b) The article does not provide information about similar incidents happening at other organizations or with their products and services. Hence, there is no mention of the software failure incident occurring again at multiple organizations.
Phase (Design/Operation) unknown The article does not specifically mention any software failure incident related to the development phases (design or operation). Therefore, the information needed to determine whether the failure was due to design or operation factors is unknown.
Boundary (Internal/External) within_system The software failure incident reported in Article 87005 is related to a wiring harness issue in Mazda vehicles. The failure is within_system as it is caused by a "weak retention force" in some wiring harness connector terminals within the vehicle's electrical system, leading to disruptions between different control modules [87005].
Nature (Human/Non-human) non-human_actions (a) The software failure incident in the article is related to non-human actions. The issue stemmed from a "weak retention force" in some wiring harness connector terminals, causing disruptions between different control modules in the car, leading to problems like turn signals not working, engine not restarting, or the passenger-side front airbag not deploying in a crash. These issues were not directly caused by human actions but rather by a flaw in the wiring harness connectors [87005].
Dimension (Hardware/Software) hardware (a) The software failure incident in the article is related to hardware. The issue stems from a "weak retention force" in some wiring harness connector terminals, causing disruptions between different control modules in the car [87005]. This hardware-related problem leads to various issues such as turn signals not working, engine not restarting, and passenger-side front airbag not deploying, highlighting the hardware origin of the failure.
Objective (Malicious/Non-malicious) non-malicious (a) The software failure incident reported in Article 87005 is non-malicious. The failure is attributed to a "weak retention force" in some wiring harness connector terminals in Mazda vehicles, causing disruptions between different control modules in the car. This issue leads to various problems such as turn signals not working, engine not restarting, or the passenger-side front airbag not deploying in a crash. Mazda has initiated a recall to address these safety hazards, indicating that the failure was not due to malicious intent but rather a technical flaw in the wiring harness connectors [87005].
Intent (Poor/Accidental Decisions) unknown The article does not mention any specific software failure incident related to poor decisions or accidental decisions. Therefore, the intent of the software failure incident in this case is unknown.
Capability (Incompetence/Accidental) unknown The article does not mention any software failure incident related to development incompetence or accidental factors. Therefore, the information to answer this question is 'unknown'.
Duration unknown The article does not mention any software failure incident related to the duration of the failure being permanent or temporary. Therefore, the information to determine whether the software failure incident was permanent or temporary is unknown.
Behaviour crash, omission, other (a) crash: The article mentions that in some cases of the software failure incident related to the Mazda recall, the engine might not restart, indicating a failure due to the system losing state and not performing its intended functions [87005]. (b) omission: The article highlights that in some cases of the software failure incident, the turn signals may stop working, indicating a failure due to the system omitting to perform its intended functions at an instance(s) [87005]. (c) timing: The article does not provide information on the software failure incident being related to timing issues. (d) value: The article does not mention the software failure incident being related to the system performing its intended functions incorrectly. (e) byzantine: The article does not mention the software failure incident being related to the system behaving erroneously with inconsistent responses and interactions. (f) other: The other behavior mentioned in the article is related to the passenger-side front airbag not deploying in a crash, which represents a unique safety hazard and could be categorized as a failure due to the system behaving in a way not described in the options (a to e) [87005].

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. The article mentions that due to the wiring harness issue in some Mazda vehicles, there is a risk that the passenger-side front airbag may not deploy in a crash. This poses a safety hazard as it could potentially harm passengers in the event of an accident. However, it is noted that Mazda has not received any reports of accidents or injuries related to this defect [87005].
Domain transportation The software failure incident reported in Article 87005 is related to the transportation industry. Mazda announced a recall for the 2018 Mazda CX-9 crossover due to issues with the wiring harness connectors that could disrupt communication between different control modules in the car, leading to various safety hazards such as malfunctioning turn signals, engine failure, and potential non-deployment of the passenger-side front airbag [87005]. This incident directly impacts the transportation sector as it involves a vehicle model and its electrical system, which is crucial for the safe operation of the vehicle.

Sources

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