PCBA and SMT Audit Types AmrepMexico Offers

Audit type When to use it What it focuses on
Qualification audit Before awarding volume to a new EMS supplier Whether every station can build your product's technology
Periodic process audit On a schedule set by product risk Whether the line still runs the qualified process
Change-triggered audit After a line, equipment, material, or program change Whether the change weakened controls that already worked
Problem-driven audit After a field failure, complaint, or yield drop Only the stations tied to the defect data

SMT and PCBA Control Points AmrepMexico Audits in Mexico

Solder Paste Storage and Handling

We audit paste refrigeration, thaw time, mixing, open time, and lot traceability. Each step is compared against the paste manufacturer's data sheet and the supplier's procedure. You learn whether paste reaches the printer in the condition the process was qualified with.

Stencil Design and Maintenance

We review aperture design against IPC-7525 area ratio guidance, along with tension records, cleaning frequency, and revision control. Damaged or worn stencils are checked against the supplier's retirement criteria. You learn whether print defects start before the first board is loaded.

Paste Printing and SPI

We audit print parameters, SPI limits for volume, height, and offset, and how SPI data feeds back to printer adjustments. Capability on critical pads is reviewed using actual SPI data, not summary reports. You learn whether printing is controlled or only inspected.

Component Placement

We verify feeder setup confirmation, placement program revision control, nozzle maintenance, and first-piece approval. Machine capability records are checked against IPC-9850 characterization practices. You learn whether the right part lands in the right place on every changeover.

Reflow Profiling

We audit profiling frequency, thermocouple placement per IPC-7530, peak temperature, time above liquidus, and nitrogen use where it applies. Zone setpoint changes are traced to approved profile revisions. You learn whether the oven still runs the profile the product was validated on.

Wave and Selective Soldering

We audit flux application, preheat, contact time, pallet condition, and solder pot contamination analysis against J-STD-001 limits. Selective solder programs are checked for revision control and nozzle maintenance. You learn whether through-hole joints come from a controlled process.

Hand Soldering Stations

We verify tip temperature checks, iron grounding, flux control, and operator certification to J-STD-001. Each station's work instructions are compared against the components actually being soldered. You learn whether manual operations carry the same control as automated ones.

Inspection Gate Placement and Defect Review

We assess where AOI sits in the line, who approves program changes, and how flagged defects are reviewed and repaired. Defect data is checked to confirm it reaches process engineers and not just the repair bench. You learn whether inspection drives prevention or only sorting.

Bare Board Storage and Handling

We audit PCB storage, moisture protection, bake practices, and handling against IPC-1601. Boards on the line are checked for exposure time and contamination risk. You learn whether board condition is adding defects before assembly begins.

Traceability and Changeover Control

We test traceability by tracing one serial number back to its paste lot, component reels, profile, and operator during the audit. Line clearance and changeover records are reviewed for mixed parts and leftover components. You learn whether the supplier can isolate a problem lot quickly.

Work Instructions and Operator Training

We compare work instructions at each station against current drawings and program revisions. Training records are matched to the operators actually working the line. You learn whether your process knowledge reaches the people building your product.

Audit Your EMS Supplier's Line

How AmrepMexico Scores and Classifies Audit Findings

Each control point is scored against objective evidence collected on the floor, including records, machine settings, data, and direct observation. Findings are then classified by risk to your product.

Classification Meaning Required response
Major nonconformance A missing or failed control that can ship defective product Containment before the next shipment, plus a corrective action plan
Minor nonconformance A partial or inconsistent control with limited product risk A corrective action plan within the agreed timeframe
Observation A weakness that could become a nonconformance Review at the next audit
Improvement opportunity A practice that could raise yield or efficiency Optional supplier action

The overall audit score shows supplier maturity. The finding classes show where action is needed first.

Our SMT Audit Process, From Kickoff to Closeout

1. Pre-Audit Questionnaire

We send the supplier a questionnaire tailored to your product, technology, and requirements. The answers shape the audit plan before anyone arrives on site.

2. Recipe and Document Review

We review process recipes, profiles, control plans, and procedures before the line walk. Gaps on paper become questions to test on the floor.

3. On-Line Evidence Collection

We walk every station, observe live production, and interview operators in Spanish. Evidence comes from what the line actually does, not from what the supplier says it does.

4. Closing Meeting and Report

We present findings to supplier management on the final day. The formal report follows with classifications and required responses.

5. Corrective Action Verification

We return to the line to confirm each corrective action is implemented and effective. Findings close on evidence, not on the supplier's word.

Plan Your Audit Scope

Audit Criteria Matched to Your Customer Requirements

Requirement source What the audit adds
IPC J-STD-001 Baseline soldering process and material controls
VDA 6.3 Automotive process audit scoring and element structure
IATF 16949 customer-specific requirements OEM-specific controls for automotive modules
ISO 13485 Verification that validated processes haven't changed
AS9100 Aerospace production and configuration controls
Your internal checklist Your own control points, applied by an independent auditor

Why EMS Buyers Trust AmrepMexico Auditors

Evidence Over Interviews

Our auditors verify claims against records, machine settings, and live production. A finding stands only when the evidence supports it.

Operator Interviews in Spanish

Interviewing operators in their own language shows how work is actually done on each shift. It also uncovers gaps a translated interview would miss.

Independent of Your Supplier

AmrepMexico has no commercial tie to the EMS providers we audit. Findings reflect the line as it is, not as the supplier would like it scored.

Follow-Through After the Report

We stay engaged until corrective actions are verified at the line. An audit only adds value when its findings close.

Rooted in Mexican Industry Since 1994

As part of the global AMREPInspect group, AmrepMexico has supported Mexican manufacturing since 1994. Our senior engineers bring more than 20 years of hands-on experience in Mexican production environments.

Where AmrepMexico Performs SMT Audits in Mexico

We perform PCBA supplier audits in Mexico wherever your EMS lines operate, including Guadalajara, Tijuana, Mexicali, Ciudad Juárez, Chihuahua, Monterrey, Reynosa, Nogales, Querétaro, San Luis Potosí, Mexico City, and Puebla.

Feedback From AmrepMexico Clients

I was looking for a quality inspection service where I could trust the inspection results and be in compliance with all the quality regulations in place. The team of experts at AmrepMexico is able to provide this service with their in-depth knowledge of the industry and their high-level experience. They have the expertise to handle any type of inspection, from a one-off shipment to a complex project.

Saurabh Karangutkar

AMREP is one of my top 3 best supplier companies to work with. They have provided a great quality of service and have been able to get the job done and still provide the quality that is needed.

Jack Martem

I needed to find an inspection company that has experts who can help me with my tech gadgets. I needed a local company in Mexico, one that has an outstanding reputation and is reasonably priced. I hired AMREP Mexico to inspect my smart LED lights, and they did a great job. I can't see anything wrong with how they handled my inspection, and I will use them again in the future.

Natalia Skylar

PCBA and SMT Process Audit FAQs

How long does an SMT process audit take?

It depends on the number of lines, products, and process steps in scope. A focused problem-driven audit takes less time than a full qualification audit across several lines. We confirm the duration during scoping so your supplier can plan production around it.

Will the EMS supplier know the audit is coming?

Usually, yes. Most audits are announced so the right people and records are available. Your purchase terms may also allow short-notice audits, which give a more realistic view of daily practice.

How is a process audit different from an IPC-A-610 inspection?

IPC-A-610 inspection judges finished assemblies against acceptance criteria. A process audit examines the inputs, settings, and controls that produce those assemblies. Inspection finds defects, while the audit finds why they happen.

Can you audit using our company's checklist?

Yes. We can apply your internal checklist, the AmrepMexico SMT audit checklist, VDA 6.3, or a combination of them. Using your checklist keeps results comparable with audits your team has run at other suppliers.

What if the supplier disputes a finding?

Each finding is tied to recorded evidence and the governing clause, so disputes are settled on facts. If disagreement remains, the evidence goes to your quality team for a final decision.

Can you audit the bare PCB fabricator too?

Yes, when the fabricator is part of your audit scope. Board issues with plating, solder mask, or moisture can look like assembly defects, so auditing both suppliers isolates the true cause.

Audit Your Mexico SMT Line with AmrepMexico

Tell us about your product, EMS supplier, and audit goals, and we'll define an audit scope built around your risks.

Book Your SMT Process Audit