AIAG CQI-15 Welding System Assessment: Audit Pass Checklist

Automotive OEM customers audit their welding suppliers with increasing rigour. AIAG CQI-15 is the benchmark they use most often — and a single Critical element scored Unacceptable is enough to fail the entire assessment, regardless of how well everything else performs. This guide translates the CQI-15 framework into a practical, category-by-category checklist that quality and manufacturing engineers can work through before the auditor arrives.

What Is AIAG CQI-15?

The Automotive Industry Action Group (AIAG) publishes the Welding System Assessment (CQI-15) as part of its family of special process assessments, alongside CQI-11 (plating), CQI-12 (coating), and CQI-23 (molding). First released in 2011 and periodically updated, it is the de facto audit template referenced in Ford, GM, and Stellantis supplier quality manuals.

CQI-15 applies to any welding process used in regulated automotive programs: resistance spot, projection, seam, GMAW, GTAW, plasma, and laser. It evaluates the system — not just individual welds — covering equipment, process control, documentation, personnel, and continual improvement.

CQI-15 Scoring Framework

Each audit element receives one of four ratings:

Critical elements carry a veto: a score of 1 on any Critical item fails the audit outright. These elements typically cover process parameter monitoring, calibration currency, and documented corrective action closure.

Target score: customer-specific, but generally ≥3.0 average with no Critical element below 3.

A score of 2 on a non-Critical element triggers a formal corrective action plan (CAP) with an agreed closure date — usually 90 days or before next scheduled production run.

Pre-Audit Checklist — Five Control Areas

1. Process Parameters and Control Plans

Process control is where most audit failures originate. Auditors verify that every production welding operation has a current control plan aligned to the approved PPAP submission, and that the control plan parameters match what is actually running on the line.

• Control plan current revision matches PPAP submission
• All parameters (current, voltage, wire feed speed, travel speed, shielding gas flow) have documented tolerances
• Parameter tolerances based on weld qualification data — not estimated
• Out-of-tolerance response defined (stop production, quarantine, escalate)
• Process change history documented with re-approval evidence where required

2. Equipment Calibration and Maintenance

• All measurement and monitoring devices on calibration schedule
• Calibration records traceable to NIST (or equivalent national standard)
• Calibration due dates visible at point of use (labels or digital dashboard)
• Preventive maintenance plan active, last PM date recorded
• Equipment capacity verified against production demand (no deferred maintenance flagged as “acceptable”)

3. Documentation and Traceability

• Weld maps for all assemblies — each weld spot or joint labelled with type, class, and accept/reject criteria per ISO 5817 or equivalent
• WPS (Welding Procedure Specification) available at each welding station
• PQR (Procedure Qualification Record) on file and traceable to WPS in use
• Incoming material traceability: heat/lot numbers linked to production records
• Non-conformance records retained ≥ customer-specified retention period (often 15 years for safety parts)

4. Corrective Actions (CAPs)

Open or overdue corrective actions are a red flag in any audit. Auditors check both closure rate and effectiveness of past CAPAs.

• All open CAPs have assigned owners, target dates, and current status
• Closed CAPs have verification evidence (re-measurement, production data, re-audit sign-off)
• No repeat failures for the same root cause within 12 months
• 8D or equivalent format used for Critical and Major non-conformances
• Customer-facing corrective actions mirror internal actions (no separate “audit copy”)

5. Operator Qualification and Training

• All production welders qualified to applicable standard (AWS D1.1, ISO 9606-1, or process-specific)
• Qualification certificates current (re-qualification interval not exceeded)
• Training records for process-specific parameters (e.g., resistance spot welding setup) on file
• Visual inspection competency verified — inspectors certified or demonstrably trained to written criteria
• On-the-job training records signed by both trainer and trainee

Common CQI-15 Failure Modes

Understanding where suppliers typically fail helps focus pre-audit effort on highest-risk areas.

Calibration gaps: Equipment used for process monitoring (clamp force testers, weld timer analyzers, thermal measurement devices) frequently falls off calibration schedules during high-volume production periods. One expired calibration on a Critical device fails the element.

Control plan-to-floor divergence: The approved PPAP control plan specifies parameters that drift over time — wire feed speeds adjusted for consumable changes, gas flow rates set by feel, interpass temperature limits not actively checked. Auditors compare documented values to current SPC data or production travellers.

CAP documentation gaps: Many suppliers close corrective actions internally but fail to link closure evidence to the original non-conformance record. Auditors follow the thread from problem identification through root cause, containment, and permanent corrective action; any broken link is a finding.

Welder qualification expiry: Annual or biennial re-qualification intervals are short relative to a busy production calendar. Automotive suppliers running multiple qualifications across large welder populations frequently have 10–15% expired at any given time.

Digital Evidence That Auditors Look For

Modern CQI-15 auditors increasingly expect continuous process evidence, not just periodic inspection records. Moving from paper travellers and manual logbooks to real-time monitoring closes the most common audit gaps:

• Timestamped parameter logs correlated to part serial numbers prove that each assembly ran within specification — not just that the line was in-spec at the last check.
• Automated out-of-tolerance alerts with documented response actions demonstrate that the out-of-tolerance response in the control plan is actually implemented.
• Trend data showing drift over time before it becomes a rejection supports the “continual improvement” section of CQI-15.

Thermal imaging systems integrated into the welding cell provide weld-by-weld evidence of heat input consistency, HAZ geometry, and cooling rate — data that maps directly to the process parameter control elements of the assessment. See our companion guide on CQI-15 digital monitoring strategy for implementation specifics.

CQI-15 vs ISO 3834 Alignment

Many Tier-1 suppliers must satisfy both CQI-15 (customer-driven) and ISO 3834 (contractual or internal quality standard). The frameworks are complementary, not redundant:

Satisfying ISO 3834-2 (comprehensive requirements) typically brings a supplier close to CQI-15 Acceptable on all documentation and qualification elements, reducing first-audit risk. The gap is usually in automotive-specific elements: PPAP linkage, customer-specific parameter limits, and OEM-format CAPA.

For a combined audit checklist covering both frameworks, see ISO 3834 and EN 1090 audit preparation guide.

Preparing for the Audit

Three actions deliver the highest return in the weeks before a CQI-15 assessment:

1. Run a qualification expiry sweep across all active welders and inspectors. Renew anything expiring within 90 days before the audit date.
2. Walk the control plan vs the floor — have a second engineer (not the author of the control plan) verify each parameter live at the machine and flag any divergence.
3. Close or formally defer all open CAPs — auditors interpret open items as unresolved non-conformances. Documented deferrals with OEM approval are acceptable; silently open items are not.