Auto-Sector Interview Preparation

QA is process-oriented and proactive — it builds quality into processes to prevent defects (audits, procedures, training). QC is product-oriented and reactive — it inspects and tests finished products to detect and remove defects. QA prevents; QC detects.

IATF 16949 is the global quality management standard for the automotive industry, built on ISO 9001 with automotive-specific requirements. It emphasises defect prevention, reducing variation and waste in the supply chain, and continual improvement. It's mandatory for most OEM suppliers.

FMEA (Failure Mode and Effects Analysis) is a structured method to identify potential failure modes in a design (DFMEA) or process (PFMEA), assess their effects, severity, occurrence, and detection, compute a Risk Priority Number (RPN), and prioritise preventive actions before failures occur.

RPN = Severity × Occurrence × Detection. Severity rates the impact of the failure (1–10), Occurrence the likelihood it happens (1–10), and Detection how likely current controls catch it before reaching the customer (1–10, where 10 = hard to detect). Higher RPN = higher priority.

8D (Eight Disciplines) is a structured team approach to solving problems: D1 form team, D2 describe problem, D3 interim containment, D4 root-cause analysis, D5 choose corrective actions, D6 implement and validate, D7 prevent recurrence, D8 recognise the team. Widely used for customer complaints.

PPAP (Production Part Approval Process) is the standardised process to demonstrate a supplier can consistently produce parts meeting requirements. It's submitted before mass production or after changes, with documents like the part submission warrant, dimensional results, control plan, and FMEA across 18 elements.

A non-conformance is any deviation from a specified requirement. A defect is a non-conformance that affects fitness for use or safety — i.e. it impacts the customer's ability to use the product as intended. All defects are non-conformances, but not all non-conformances are defects.

SPC uses control charts to monitor a process over time, distinguishing normal common-cause variation from abnormal special-cause variation. It helps detect when a process is going out of control before defects occur, enabling timely correction and reducing variation.

Cp measures process capability — how well the process spread fits within specification limits (assuming centred). Cpk also accounts for how centred the process is relative to the spec limits. Cpk ≤ Cp; a Cpk of 1.33 is commonly required in automotive, indicating a capable, well-centred process.

Check sheet, Pareto chart, cause-and-effect (Ishikawa/fishbone) diagram, histogram, scatter diagram, control chart, and stratification (or flowchart). These basic tools help collect, analyse, and visualise quality data for problem-solving.

A control plan is a documented description of the systems and processes used to control a part or process — listing characteristics, specifications, measurement methods, sample size/frequency, and reaction plans. It ensures consistent quality and is a key PPAP element.

Root cause analysis identifies the fundamental cause of a problem rather than its symptoms. A common technique is the '5 Whys' — repeatedly asking 'why' until reaching the root cause. The fishbone diagram is another, categorising causes (Man, Machine, Material, Method, Measurement, Environment).

Calibration compares an instrument against a traceable standard and adjusts it to ensure accuracy. Verification simply confirms the instrument still meets required accuracy without necessarily adjusting it. Both are needed to ensure reliable measurements (part of MSA).

MSA evaluates whether a measurement system is reliable — assessing bias, linearity, stability, repeatability, and reproducibility (Gage R&R). It ensures measurement variation is small relative to the tolerance, so decisions based on measurements are trustworthy.

Poka-Yoke (mistake-proofing) is a mechanism that prevents errors or makes them immediately obvious — e.g. a connector that only fits one way, or a fixture that won't allow a part loaded incorrectly. It eliminates defects at the source rather than catching them later.

Variable data is measured on a continuous scale (length, weight, torque) and gives more information. Attribute data is categorical — pass/fail, go/no-go, number of defects. Variable data needs smaller samples for the same confidence; attribute data is simpler to collect.

APQP (Advanced Product Quality Planning) is a structured framework for developing products that satisfy the customer, covering five phases: plan and define, product design and development, process design and development, product and process validation, and feedback/corrective action. PPAP is its output.

A quality audit is a systematic examination to verify conformance to requirements. Types: product audit (inspect the product), process audit (verify the process is followed), and system audit (assess the overall quality management system). Audits can be internal (first-party), supplier (second-party), or certification (third-party).

FTR means producing a part correctly the first time without rework or scrap. It matters because rework and scrap add cost, delay, and risk; high FTR indicates a capable, well-controlled process and directly improves productivity and profitability.

COPQ is the total cost incurred due to defects — internal failures (scrap, rework), external failures (warranty, recalls, lost customers), appraisal costs (inspection), and prevention costs. Quantifying COPQ highlights the business case for investing in prevention.