FailModeLens

FMEA and FMEDA are distinct analyses. FMEA identifies systematic software failures. FMEDA quantifies random hardware failure rates. Your software FMEA should cross-reference but not replace the hardware FMEDA. Guide: orbitaljump.com/fmea-analysis/… #FMEA

Occurrence ratings in software FMEA are not about PPM rates. The question is: can the triggering condition ever occur in the operational design domain? That is a very different question than how often has this failed in the field.

Software engineers encountering ISO 26262 often ask: how do I assign FMEA ratings to code? Hardware failure modes like cracking do not translate. Here is what does:

Most common FMEA audit findings: High AP rows with no closure evidence, FMEA revision dates from initial PPAP never updated, CCs in DFMEA not traceable to PFMEA. What to document and when: orbitaljump.com/fmea-analysis/… (4/4)

How auditors trace it: pick a CC from the DFMEA, find it in the PFMEA, find it in the control plan with a detection method, confirm SPC is running. Missing any link = nonconformance. The chain has to be intact, not just the individual documents. (3/4)

IATF 16949 FMEA requirement is not in one clause—it lives in Clause 8.3.3.3 (Special Characteristics), Clause 8.5.1.1 (Control Plan), and customer-specific requirements from every major OEM. Here's how they connect. (1/4)

Software FMEA for ISO 26262 looks nothing like hardware FMEA. Value errors, timing failures, commission errors, omission, and interface corruption are the five failure mode categories for safety-critical code. orbitaljump.com/fmea-analysis/… #FMEA #ISO26262

IATF 16949 R15 requires FMEA software—not Excel. Third-party auditors often skip it; German OEM customer audits don't. What R15 actually requires and how auditors trace DFMEA to PFMEA to Control Plan: orbitaljump.com/fmea-analysis/… #IATF16949 #FMEA

Every action leaving the session needs: an owner (person, not department), a target date, a specific description. Evaluate options is not an action. Meeting structure breakdown: orbitaljump.com/fmea-analysis/… (4/4)

Severity disagreements = debate over which effect to rate. Rule: rate the worst-case effect at system/regulatory level, not the most likely. Occurrence disagreements = need data. Table the rating, assign someone to pull Cpk, mark for re-rating. (3/4)

Most FMEA team sessions run long not because risk analysis is hard—but because nobody agreed on the agenda before walking in. Guide to running a cross-functional FMEA review meeting that produces results, not just rescheduled sessions. (1/4)

FMEA review sessions fail from poor structure, not poor methodology. 20 min explaining what changed. Ratings debated without criteria on screen. Actions with no owners. Better structure guide: orbitaljump.com/fmea-analysis/… #FMEA #QualityEngineering

Severity can only be reduced by changing the design—not by adding process controls. PFMEA teams who debate severity down because inspection catches it are misusing the scale. Full breakdown + APQP timing table: orbitaljump.com/fmea-analysis/… (4/4)

The key linkage: DFMEA failure modes become PFMEA causes. Critical Characteristics from DFMEA must flow into PFMEA and control plan. Auditors trace this chain. Missing traceability = nonconformance, even if both documents look complete individually. (3/4)

DFMEA vs PFMEA: practitioners know both types, but confuse the directionality. Here's what actually transfers between them and when each document should exist in your APQP timeline. (1/4)

Full guide: function-based DFMEA structure, verb-noun syntax, cause-mode-effect separation: orbitaljump.com/fmea-analysis/…

Verb-noun syntax forces specificity. Bracket fails tells you nothing. Bracket fails to maintain motor-gearbox alignment under load tells you which function is at risk and what failure looks like. Specificity is what audits actually test.

Most common DFMEA quality issue is not missed failure modes — it is mis-written ones. Bracket cracks is a cause. NVH issue is an effect. Failure mode is the way the function fails. Most teams confuse the three and do not know it.