Evaluation of Quality Management Practices in a Vehicle Assembly Plant in Lagos State

The quality of locally assembled vehicles in Nigeria's growing automotive assembly sector is a strategic concern for consumer confidence, regulatory compliance, and the long-term competitiveness of domestic manufacturers against imported alternatives. This study evaluates the quality management practices of a vehicle assembly plant in Apapa, Lagos State, with reference to the requirements of ISO 9001:2015 and automotive sector-specific quality frameworks. A structured audit methodology was applied, combining document review of quality manuals, procedures, and inspection records, interviews with quality assurance and production management personnel, and direct observation of assembly line quality control checkpoints. Compliance was assessed across quality management system elements including process control, inspection and testing, calibration, corrective action, and management review. Overall compliance with ISO 9001:2015 requirements was scored at 74 percent, with the weakest performance recorded in statistical process control application and supplier quality management. Customer warranty claim analysis revealed that paint defects, electrical system faults, and suspension alignment issues accounted for 68 percent of all warranty returns within the first year. Root cause analysis for the leading defect categories was conducted, identifying key process control gaps including inadequate incoming inspection of body panel supplies and inconsistent torque application at critical fastener joints. The study recommends targeted process improvement interventions and a structured supplier development programme. Keywords: quality management, vehicle assembly, ISO 9001, warranty claims, Lagos State.