Follow the evidence.
Confirm the cause.
SFBDM provides a structured approach to industrial troubleshooting, from signal observation and root cause analysis to corrective decisions and post-repair validation. It connects evidence-based decisions, traceable records, and the development of your team’s diagnostic capability.
Explore the five diagnostic stages
Five stages.
A traceable decision at each step.
Each stage connects what the team observes with the next diagnostic decision. Practical activities are built around relevant equipment and documented failure scenarios.
01 Fault Identification
Observe the system before forming a conclusion.
Record the operating condition, visible symptoms, and relevant electrical, pneumatic, or hydraulic signals. Distinguish the initial symptom from other observed behavior.
Illustrative pneumatic scenario
The actuator reaches its end position later than the cycle requires. Record the expected and observed travel time, operating conditions, sequence, and position feedback. Keep the symptom separate from any proposed cause.
What this stage produces
An observation record that supports the next diagnostic step.
02 Signal Interpretation
Turn observations into ranked hypotheses.
Compare signal combinations with documented failure patterns and expected system behavior. Identify what each observation supports and what remains unresolved.
Illustrative pneumatic scenario
Consider air-supply conditions, valve response, flow restriction, and mechanical resistance. Plan checks of supply pressure during movement, command and position signals, the flow-control setting against the approved setup, and relevant mechanical conditions. Record which evidence supports or weakens each hypothesis.
What this stage produces
A ranked hypothesis set, with evidence and remaining checks.
03 Root Cause Analysis
Trace the condition that produced the fault.
Investigate the causal chain and contributing conditions. Use measurements and functional observations to distinguish the failed behavior from its originating cause.
Illustrative pneumatic scenario
For this example, assume the checks show supply pressure within the specified operating range, the expected valve command and response, and a flow-control setting that differs from the approved setup. These findings support excessive restriction as the immediate cause to test. Investigate why the setting changed by reviewing available setup and maintenance records; document any unresolved origin instead of claiming a confirmed root cause.
What this stage produces
A causal explanation that separates supported findings, contributing conditions, and unresolved questions.
04 Intervention Selection
Choose a correction supported by the diagnosis.
Select an intervention that addresses the confirmed cause. Record the rationale and consider the equipment requirements and agreed operational conditions.
Illustrative pneumatic scenario
Select restoration of the approved flow-control setting as the intervention to test, following the equipment requirements and agreed procedure. Document the supporting evidence. Address any confirmed setup or maintenance issue that allowed the deviation; retain unresolved questions for follow-up.
What this stage produces
A justified intervention decision tied to the confirmed cause.
05 Post-Repair Validation
Confirm resolution and record the full cycle.
Check the intervention against predefined acceptance criteria. Distinguish restored function from resolution of the originating condition. Record system behavior, residual issues, and findings for future diagnostic use.
Illustrative pneumatic scenario
Compare actuator travel time and position feedback before and after the intervention under the defined operating conditions. If the acceptance criteria are met, record restored function. Close the diagnostic record only with a clear account of any unresolved cause, remaining deviation, and assigned follow-up.
What this stage produces
A validation record with acceptance results, limitations, and follow-up actions.
Evaluate the reasoning and the execution.
Criteria are defined for each activity and matched to the capability being developed.
- Interpret the systemRead diagrams and technical information. Identify expected signal and component behavior.
- Observe and measureCapture relevant observations and measurements with enough clarity to support hypotheses.
- Investigate and explainCompare possibilities, trace the cause, and explain the basis for the corrective decision.
- Verify and documentCheck circuit or system behavior and record the diagnostic cycle, remaining gaps, and next actions.
How the work is recorded
Implementation records connect systems and fault scenarios with practical activities, observed team performance, difficulties, and follow-up actions. Documentation is defined within the engagement scope.
Built from applied technical experience.
Felipe Marins developed the SFBDM approach drawing on industrial diagnostic practice and technical capability development, including his career at SENAI in Brazil.
Institutional references include contextualized problem-solving, circuit simulation and assembly, technical documentation, and observed practical assessment. CENATEC adapts the diagnostic approach to the needs and equipment of each engagement.
See implementation scope and deliverablesLet’s discuss your diagnostic challenges.
Tell us about recurring faults, the equipment involved, and where your team needs stronger diagnostic capability. We can discuss how an SFBDM engagement could fit your operation.