A troubleshooting guide is organised by symptom, not by cause, and for each symptom it lists the cheapest check first, the likely causes, how to confirm each and when to stop and call someone. It must also flag the symptoms where diagnosing a running machine is itself the danger, such as anything involving pressure, and for those the entry says only to shut off the energy source and let the machine come to rest before looking.
Writing down the experience of diagnosing faults so that a less experienced person can use it, including the faults that must not be diagnosed live.
Symptoms Are What The Operator Actually Sees
The carrier article’s rule is to keep troubleshooting guides separate from procedures and to organise them by symptom. Its examples: “the metal cracks when hammered”, with possible causes of too cold, wrong alloy or hammering too hard; “the bread doesn’t rise”, with dead yeast, water too hot or not enough kneading; “the joint is weak”, with wrong angle, insufficient peg depth or green wood. The carrier says these guides capture experiential knowledge that takes years to develop and is the most at risk of being lost.
This is the knowledge the Knowledge Preservation article calls diagnostic judgement: how an experienced practitioner recognises a problem and decides in a non-standard situation, harder to document because it is intuitive. A guide does not replace the judgement, but it gives a beginner a structured start.
The Shape Of An Entry
- Symptom in the operator’s words.
- Stop test: does this symptom mean stop now? If it involves pressure, fire, a failing structure or a person at risk, say so first.
- Cheapest check first: the vent is blocked, the fuel is wet, the tool is dull.
- Likely causes in order, with how to confirm each.
- Fix, or who to call if it is outside the operator’s level.
- What to record in the log, so the pattern is visible later.
The Failure Diagnosis article adds a habit worth building in: a failed part is evidence, its wear or fracture pattern pointing to overload, misalignment, bad lubrication or a flawed material. Keep the part.
Worked Example: A Few Autoclave Entries
These entries name no pressure or time of their own. Values come from the vessel’s nameplate, log and schedule.
| Symptom | Stop now? | First check | Likely causes |
|---|---|---|---|
| Gauge reads working pressure, thermometer reads low | No; do not start the hold | Air in the chamber | Air not purged; vent closed too early (Medical Instrument Sterilization) |
| Steam jetting at the door edge | Yes: heat off, let it cool | Do not touch the joint | Hard or damaged gasket, dirty face, uneven closure (Gasket Seating and Flange Finish) |
| Relief valve lifting at normal pressure | Yes: heat off | Is the heat too high? | Heat source too strong, seat dirty or damaged, setting too close to operating pressure (Pressure Relief Valve) |
| Door will not release after cooling | Yes: leave it shut | Gauge reads zero? | Interlock sensing port blocked; vacuum from cooling; never force it (Door Interlock) |
| Chemical indicator did not change | The load is not sterile | Thermometer log | Air pocket, load packed too tight, too short a hold; re-run |
| Packs come out wet | No | Exhaust speed | Exhausted too fast; the carrier recommends a slow exhaust over about ten minutes |
The entries marked “Yes” have one rule in common: shut off the heat and let the vessel cool and depressurise before anything is examined.
What You Need
- A log of real faults, including near misses. This is the raw material.
- The experts, interviewed about their last ten problems.
- A format that can be read by a beginner under stress.
- A review step by a second practitioner.
Method: Building A Guide
Step 1: Collect symptoms from the log and from the people who do the work.
Step 2: Interview the expert for each: what do you check first, and why?
Step 3: Order the checks cheapest and safest first.
Step 4: Mark the stop symptoms.
Step 5: Test on a newer person with a past problem; revise where they got lost.
Step 6: Add new entries after every real fault, as part of closing the incident.
Common Mistakes
- Organising by cause. The operator does not know the cause.
- Long lists with no order.
- No stop flag, so a beginner diagnoses a hot pressurised vessel.
- Copying numbers from a different machine.
- Never updating.
What’s Next
- Learn next: Oral Tradition Integration — the stories and sensory cues that the table cannot hold
- Combine with: Procedure Documentation — the routine side of the same knowledge