Troubleshooting & Failure Investigation Forms
The 25 forms that convert an AGL abnormal condition or failure into a controlled engineering record — Fault → Diagnosis → Evidence → Failure Mode → Root Cause → Corrective Action → Preventive Action → Verification → Closure → Lessons Learned → Reliability Intelligence. Grouped into Fault & Failure Investigation, Root Cause Analysis, Corrective & Preventive Action, Failure Mode Records, Equipment-Specific Failure Investigation and Failure Intelligence, this division is the fault-diagnosis and root-cause layer that connects Inspection, Testing and Maintenance to the Asset Management and Failure Database.
Where this fits — Inspection, testing and maintenance records tell you that something is wrong; this division tells you why — and what to do so it does not happen again. Every investigation here should trace back to an Inspection No., Test Report No. or Work Order, and feed forward into the Failure Closure Certificate and, ultimately, the asset's reliability history, condition-based maintenance strategy and lifecycle replacement plan.
A · Fault & Failure Investigation
4 of 4 formsFIR-01 Fault Investigation Form Form
Purpose
Initiates a structured investigation whenever an AGL fault, abnormal condition or equipment malfunction is identified.
Key Fields
- Fault Investigation No. / date-time / project-airport / location
- Runway/taxiway, equipment/system, asset ID, circuit ID
- Work Order No. / inspection or alarm reference
- Reported symptom, first observed date/time, person reporting
- Operating condition, weather/environmental condition, operational impact, initial severity
- Visual observations, alarm indications, previous failure history
- Recent maintenance, recent installation/modification, relevant test results
- Initial conclusion: fault confirmed / not reproduced / intermittent / further diagnosis required
FIR-02 Fault Diagnostic Record Record
Purpose
Documents the step-by-step diagnostic process used to identify the source of an AGL fault.
Key Fields
- Fault ID / equipment / asset ID / circuit / technician-engineer / date-time
- Diagnostic sequence: step, test/check, expected, actual, result
- Visual, electrical, connection, functional and detailed test steps
- Test instrument, instrument ID, calibration reference
- Measurement, observation, decision, next diagnostic step
- Final diagnosis: fault identified, fault location
- Probable cause / confirmed cause
- Further investigation required (Y/N)
FIR-03 Failure Investigation Report Report
Purpose
Provides a comprehensive technical investigation of a significant equipment failure.
Key Fields
- Failure Investigation No. / asset ID / equipment / location / circuit
- Failure date/time, restoration date/time, downtime, operational impact
- Initial indication, alarm, visual and electrical symptoms, performance degradation
- Investigation evidence: inspection records, test reports, photographs, measurements
- Maintenance history, previous failures, manufacturer information, relevant drawings
- Failure mode, failure mechanism, immediate cause, contributing factors, root cause
- Corrective action, preventive action, design improvement
- Maintenance improvement, monitoring requirement
FIR-04 Breakdown Investigation Investigation
Purpose
Investigates an unexpected AGL breakdown and determines why the breakdown occurred.
Key Fields
- Breakdown ID / asset / equipment / circuit / location / date-time
- Failure indication, operational impact, response time, restoration time
- Initial condition, diagnostic findings, failed component, failure mode
- Previous maintenance, previous similar failures, environmental conditions
- Temporary restoration / permanent repair / replacement
- Testing / return to service
- Final conclusion: root cause confirmed / probable / undetermined
- Further investigation required (Y/N)
B · Root Cause Analysis
4 of 4 formsFIR-05 Root Cause Analysis Analysis
Purpose
Systematically determines the underlying cause of a significant or recurring AGL failure, following Problem Definition → Evidence Collection → Failure Mode → Immediate Cause → Contributing Causes → Root Cause → Corrective Action → Preventive Action.
Key Fields
- Problem statement / asset / failure date / failure mode
- Evidence, immediate cause, contributing factors, root cause
- Corrective action, preventive action, verification
- Responsible person, closure date
- Method selected: 5-Why / Fishbone / Fault Tree (per severity, complexity, recurrence)
- Supporting investigation reference (FIR-01 to FIR-04)
- Cross-reference to related failure records
- Sign-off: investigating engineer, engineering manager
FIR-06 5-Why Analysis Analysis
Purpose
Identifies the underlying cause of a failure by repeatedly asking "Why?" until the answer is supported by evidence rather than assumption.
Key Fields
- Problem: why did the failure occur? (with answer/evidence)
- Why 1 through Why 5, each with answer/evidence
- Immediate cause / root cause / contributing factor
- Corrective action / preventive action
- Verification that the final "Why" is evidence-based
- Facilitator / participants
- Date of analysis
- Linked RCA reference (FIR-05)
FIR-07 Fishbone Analysis Analysis
Purpose
Investigates multiple possible causes of an AGL failure across People, Equipment, Method, Material, Environment and Measurement categories.
Key Fields
- People: training, competency, human error, procedural compliance
- Equipment: component failure, aging, design limitation, manufacturing issue
- Method: installation, maintenance, testing method, SOP
- Material: incorrect material, material quality, compatibility, aging
- Environment: temperature, moisture, water ingress, corrosion, lightning, contamination
- Measurement: incorrect test method, instrument issue, calibration, interpretation
- Possible causes / evidence / eliminated causes
- Confirmed cause / root cause
FIR-08 Fault Tree Analysis Analysis
Purpose
Analyzes how combinations of events can lead to an AGL system or circuit failure, working down from the top event through intermediate and basic events.
Key Fields
- Top event: AGL system/circuit failure
- Possible branches: power supply, CCR, series circuit, cable, transformer, fixture, connector, control/ALCMS, human/maintenance failure
- Intermediate events / basic events
- AND/OR relationships
- Evidence supporting each branch
- Probability/risk where required
- Root cause
- Mitigation
C · Corrective & Preventive Action
2 of 2 formsFIR-09 Corrective Action Report Report
Purpose
Documents actions taken to eliminate the identified cause of an existing failure or defect.
Key Fields
- CAR No. / failure-defect ID / asset
- Problem / root cause
- Corrective action / responsible person / target date / completion date
- Verification: test performed, result
- Reinspection / performance verification / effectiveness check
- Status: open / in progress / completed / verified / closed
- Supporting RCA reference
- Approval
FIR-10 Preventive Action Report Report
Purpose
Prevents recurrence of a failure, or prevents a similar failure occurring on other AGL assets.
Key Fields
- PAR No. / related failure / risk identified
- Preventive action / applicable equipment or assets
- Responsible person / target date
- Possible actions: PM frequency change, inspection frequency change, design modification
- Component upgrade, installation improvement, training, SOP revision
- Spare strategy, monitoring, condition-based maintenance
- Effectiveness: implemented / verified / effective / further action required
- Approval
D · Failure Mode Records
3 of 3 formsFIR-11 Failure Mode Record Record
Purpose
Creates a standardized record of how an AGL asset or component can fail, for the reliability database.
Key Fields
- Failure Mode ID / asset type / equipment / component
- Failure mode / failure mechanism / failure symptoms
- Effect / cause / detection method
- Corrective action / preventive action
- Failure category: electrical, mechanical, optical, thermal, structural
- Failure category (cont'd): cable, connector, control, environmental, human/installation
- Reliability information: frequency, severity, detectability
- Criticality / recurrence
FIR-12 Repeated Failure Report Report
Purpose
Identifies and investigates failures occurring repeatedly on the same or similar equipment.
Key Fields
- Repeated Failure ID / asset-equipment / failure count
- First failure / latest failure / failure interval
- Failure modes / maintenance history
- Common symptom / common component / common location
- Common environmental condition / common maintenance activity / common installation issue
- Final action: RCA required / design review / vendor review
- PM modification / replacement / monitoring
- Responsible person / target closure
FIR-13 Intermittent Failure Report Report
Purpose
Documents failures that occur irregularly or cannot be consistently reproduced.
Key Fields
- Fault ID / equipment / asset / circuit
- First occurrence / occurrence frequency / duration / operating condition
- Investigation: temperature, moisture, load, vibration
- Electrical condition, connection condition, communication, control signals, alarm history
- Diagnostic record: tests performed, test results
- Fault reproduced? Yes/No / evidence / probable cause
- Final status: cause identified / monitoring required / further diagnosis / fault resolved
- Responsible person / review date
E · Equipment-Specific Failure Investigation
9 of 9 formsFIR-14 Earth Fault Investigation Investigation
Purpose
Investigates earth faults or earth leakage conditions in AGL circuits.
Key Fields
- Fault ID / circuit / CCR / location / date-time / operating condition
- Earth resistance / insulation resistance
- Cable, transformer, connector, fixture and joint condition
- Water/moisture / physical damage
- Fault localization: circuit section, suspected component, test result, fault location
- Cause / repair / testing
- Restoration
- Preventive action
FIR-15 CCR Fault Investigation Investigation
Purpose
Diagnoses failure or abnormal performance of a Constant Current Regulator.
Key Fields
- Symptoms: no output, incorrect current, unstable current, intensity-step failure
- Alarm / protection trip / communication failure / remote-control failure / overheating
- Investigation: input supply, output current, control circuit, protection
- Internal components, cooling, alarm system
- Communication / ALCMS interface
- Fault / root cause
- Repair or replacement / test
- Restoration
FIR-16 Transformer Failure Investigation Investigation
Purpose
Investigates failure of an AGL isolation transformer.
Key Fields
- Symptoms: open circuit, insulation deterioration, overheating, physical damage
- Water ingress / connector failure / abnormal electrical condition
- Visual inspection / continuity / insulation resistance
- Connection / connector / cable
- Environmental condition / failure history
- Failure mode / cause
- Repair or replacement / test
- Preventive action
FIR-17 Fixture Failure Investigation Investigation
Purpose
Investigates failure or abnormal operation of an AGL light fixture.
Key Fields
- Symptoms: no light, flickering, reduced intensity, abnormal colour, intermittent operation
- Physical damage
- Investigation: fixture, LED/module, driver where applicable
- Transformer / connector / cable / series circuit
- Physical/environmental condition
- Failed component / failure mode
- Root cause / corrective action
- Verification
FIR-18 Cable Failure Investigation Investigation
Purpose
Investigates AGL primary/secondary cable failures.
Key Fields
- Symptoms: open circuit, earth fault, low insulation resistance, intermittent fault
- Physical damage
- Cable route / installation history / joint history
- Insulation resistance / continuity / fault location
- Environmental conditions / mechanical damage / water ingress
- Failure mechanism
- Repair / joint / replacement / test result
- Preventive action
FIR-19 Connector Failure Investigation Investigation
Purpose
Investigates AGL connector failures and connection-related faults.
Key Fields
- Connector condition / mechanical security / torque
- Corrosion / moisture / contamination
- Cable condition / connection quality / electrical test
- Failure modes: open connection, high resistance, insulation failure
- Moisture ingress / mechanical damage / corrosion
- Cause
- Replacement or repair / test
- Prevention
FIR-20 PAPI Failure Investigation Investigation
Purpose
Investigates PAPI/APAPI malfunction or abnormal performance.
Key Fields
- Symptoms: unit not operating, incorrect indication, abnormal colour transition
- Reduced output / alignment issue / electrical failure
- Power supply / fixture-unit / optical system
- Alignment / elevation / cabling
- Transformer / connector / environmental condition / previous maintenance
- Failure mode / cause
- Corrective action / alignment-test
- Verification
FIR-21 Sign Failure Investigation Investigation
Purpose
Investigates failure of illuminated airfield signs.
Key Fields
- Symptoms: sign not illuminated, partial illumination, flickering, incorrect brightness
- Physical damage
- Sign housing / light source / power supply
- Transformer / cable / connector / earthing
- Environmental condition
- Cause
- Repair or replacement / test
- Restoration / preventive action
FIR-22 ALCMS Failure Investigation Investigation
Purpose
Investigates AGL control, monitoring, communication or alarm failures.
Key Fields
- Symptoms: loss of communication, incorrect status, control failure, alarm failure
- HMI failure / PLC fault / network failure / CCR interface failure
- Power supply / PLC / HMI / network
- Communication modules / software-configuration
- CCR interface / control wiring / alarm-event logs
- Fault location / failure mode / root cause
- Corrective action / functional test
- Restoration
F · Failure Intelligence
3 of 3 formsFIR-23 Failure Trend Report Report
Purpose
Converts individual failure records into reliability and maintenance intelligence on a monthly/quarterly basis.
Key Fields
- Monthly/quarterly analysis by equipment: fixtures, CCR, transformers, cables, connectors, PAPI, signs, ALCMS
- Failures / downtime / repeat failures / MTBF / MTTR per equipment type
- Trend categories: failure frequency, failure severity, repeat failure
- Equipment age / location / manufacturer / model
- Failure mode / environmental condition / maintenance history
- Management output: high-failure assets, recurring failure modes
- Problem locations / problem equipment
- Replacement candidates / PM improvement requirements
FIR-24 Lessons Learned Record Record
Purpose
Captures engineering knowledge generated from AGL failures and investigations, so it feeds back into design, procurement, installation and maintenance practice.
Key Fields
- Lesson ID / failure-RCA reference / equipment / location
- Problem / root cause / lesson learned
- What should be changed / recommended practice
- Applicable projects/assets
- Knowledge categories: design, procurement, installation, testing, commissioning
- Knowledge categories (cont'd): maintenance, troubleshooting, safety, vendor/material, training
- Implementation: SOP updated, checklist updated, design standard updated
- Training updated / procurement specification updated / inspection frequency or PM strategy changed
FIR-25 Failure Closure Certificate Certificate
Purpose
Formally closes a failure investigation after the failure has been corrected, verified and all required actions completed.
Key Fields
- Failure ID / investigation ID / asset ID / equipment / location
- Failure date / restoration date
- Failure mode / root cause / corrective action / preventive action / RCA reference / supporting evidence
- Verification: repair completed, testing completed, functional test completed
- Equipment restored / reinspection completed / effectiveness verified
- Documentation: investigation report, test report, maintenance report, RCA, CAR/PAR, photos
- Failure history updated / asset history updated / lessons learned recorded
- Closure: closed / closed with monitoring / further action required
How Division 09 Connects
These 25 forms turn a fault, alarm or breakdown into a controlled engineering record — not just a repair log — and feed the results forward into the asset's reliability history and lifecycle plan.
Failure Investigation Flow
The six categories in this division follow the engineering sequence from detection to organizational knowledge:
Related Divisions
- Division 05 — Inspection Forms (Inspection No. that triggers a fault investigation)
- Division 06 — Testing Forms (Test Report No. used as diagnostic evidence)
- Division 08 — Maintenance Forms (Work Order / Breakdown / Repair Record that this division investigates)
- Asset Lifecycle & Failure Database (receives FIR-11, FIR-23 and FIR-25 for reliability analysis and condition-based maintenance)
Frequently Asked Questions
Quick answers about the 25 Division 09 Troubleshooting & Failure Investigation forms, how they are grouped, and how they connect to the rest of the library.
Q1What is Division 09 — Troubleshooting & Failure Investigation Forms in the AGL Engineering Forms & Templates library?
Division 09 is a set of 25 troubleshooting & failure investigation forms (FIR-01 to FIR-25) in the AGL Engineering Forms & Templates library. It converts an AGL abnormal condition or failure into a controlled engineering record, following the sequence from fault and diagnosis through root cause, corrective and preventive action, verification and closure to lessons learned and reliability intelligence. The forms are grouped into 6 categories: Fault & Failure Investigation, Root Cause Analysis, Corrective & Preventive Action, Failure Mode Records, Equipment-Specific Failure Investigation and Failure Intelligence.
Q2Which forms are included in Fault & Failure Investigation, Root Cause Analysis and Corrective & Preventive Action?
Fault & Failure Investigation (4 forms): FIR-01 Fault Investigation Form, FIR-02 Fault Diagnostic Record, FIR-03 Failure Investigation Report, FIR-04 Breakdown Investigation; Root Cause Analysis (4 forms): FIR-05 Root Cause Analysis, FIR-06 5-Why Analysis, FIR-07 Fishbone Analysis, FIR-08 Fault Tree Analysis; Corrective & Preventive Action (2 forms): FIR-09 Corrective Action Report, FIR-10 Preventive Action Report.
Q3Which forms are included in Failure Mode Records, Equipment-Specific Failure Investigation and Failure Intelligence?
Failure Mode Records (3 forms): FIR-11 Failure Mode Record, FIR-12 Repeated Failure Report, FIR-13 Intermittent Failure Report; Equipment-Specific Failure Investigation (9 forms): FIR-14 Earth Fault Investigation, FIR-15 CCR Fault Investigation, FIR-16 Transformer Failure Investigation, FIR-17 Fixture Failure Investigation, FIR-18 Cable Failure Investigation, FIR-19 Connector Failure Investigation, FIR-20 PAPI Failure Investigation, FIR-21 Sign Failure Investigation, FIR-22 ALCMS Failure Investigation; Failure Intelligence (3 forms): FIR-23 Failure Trend Report, FIR-24 Lessons Learned Record, FIR-25 Failure Closure Certificate.
Q4What is the difference between the RCA, 5-Why, Fishbone and Fault Tree forms?
The Root Cause Analysis form (FIR-05) systematically determines the underlying cause of a significant or recurring failure. The 5-Why Analysis (FIR-06) repeatedly asks why until the answer is supported by evidence rather than assumption. The Fishbone Analysis (FIR-07) investigates possible causes across People, Equipment, Method, Material, Environment and Measurement. The Fault Tree Analysis (FIR-08) analyzes how combinations of events lead to a system or circuit failure, working down from the top event.
Q5What is the difference between a Corrective Action Report and a Preventive Action Report?
The Corrective Action Report (FIR-09) documents the actions taken to eliminate the identified cause of an existing failure or defect. The Preventive Action Report (FIR-10) records actions taken to prevent recurrence, or to prevent a similar failure on other AGL assets.
Q6How is an AGL failure investigation closed and learned from?
The Failure Closure Certificate (FIR-25) formally closes an investigation after the failure has been corrected, verified and all required actions completed. The Failure Trend Report (FIR-23) turns individual records into monthly or quarterly reliability and maintenance intelligence, and the Lessons Learned Record (FIR-24) captures the engineering knowledge so it feeds back into design, procurement and maintenance.
Q7Can the forms in Division 09 be downloaded and filled in?
Yes. Each form has a Download as Word button that produces an uncontrolled sample Word template with letterhead, a document-control block, ruled entry fields and a three-tier approval table, ready to print or fill on-screen. The forms can also be searched by keyword or form ID.
Q8How does Division 09 connect to inspection, testing and maintenance?
Inspection, testing and maintenance records tell you that something is wrong, and this division tells you why and what to do so it does not happen again. Every investigation should trace back to an Inspection No., Test Report No. or Work Order, and feed forward into the Failure Closure Certificate and the asset's reliability history, condition-based maintenance strategy and lifecycle planning.
FIND THE FAULT. UNDERSTAND THE SYSTEM.
A failure investigation form is only useful if the person filling it out can actually trace a series-circuit fault, isolate a transformer failure or read a CCR alarm — not just describe the symptom.
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