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Inside the Machine G3 to G5 / Week 09 / Wednesday
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Week 09 · The troubleshooting method

Wednesday

Test one thing at a time
// Notice, name it, test one thing, write it down, ask
⏱ about 15 min

Wednesday: Test one thing at a time

A neighbor's laptop has no sound. Rocket turns up the volume, swaps the speaker and restarts, all at once. The sound comes back. "Fixed!" he cheers.

Raven asks, "What do you notice? Which change fixed it? If it breaks again, what will you do?"

Rocket frowns. He has no idea. Nova glows. "Would you like a hint? Change one thing. Check. Then change the next thing."

One change, one check

After naming the problem, you test. A test is one change you make to see if it fixes the problem.

The rule is simple: one change, then check. If it worked, stop. You found the cause.

If it did not work, undo that change. Then try the next one.

Rocket changed four things at once. The sound came back, but he learned nothing. Next time he will have to guess again.

  1. Pick the easiest safe test first.
  2. Make only that one change.
  3. Check: is the problem gone?
  4. If yes, stop and write down what worked.
  5. If no, undo the change and pick the next test.
Pick one safe test
↓
Make the change
↓ DECISION ↓
Fixed: stop and write it down
↓
Not fixed: undo it, then try the next test
ONE AT A TIME
  • Read the question.
  • Tap your answer.
Rocket changed four things at once and the sound came back. What did he learn?
You make one change and the problem is still there. What next?
Which test should usually come first?

Easy and safe tests first

Some tests are quick and safe for a child, with a grown-up nearby. Others belong only to grown-ups.

Always start with the easy, safe tests. Most problems are fixed by one of them.

ProblemEasy safe test a child may tryGrown-up only
No soundCheck volume and the mute signPlug in a different speaker
Mouse pointer will not moveTry a different mouse that is already thereReplace a battery
App is frozenClose the app and open it againInstall an update
Screen is darkPress the wake button onceCheck the charger and the plug
PUT THE NO-SOUND TESTS IN ORDER, EASIEST AND SAFEST FIRST.
  • ?Look at the volume and the mute sign
  • ?Close the app and open it again
  • ?Restart with a grown-up nearby
  • ?A grown-up plugs in a different speaker
WHY THIS EXERCISEEasy tests first means you fix most problems fast and never do more than needed.
StatementTrue or false?
Changing many things at once helps you find the cause.?
If a test does not help, undo it.?
A child may plug in a different speaker alone.?
Most problems are fixed by an easy safe test.?
WHY THIS EXERCISETesting one thing at a time makes you a technician, not a guesser.
How many things do you change in one test?
A test did not fix it. What do you do to that change before the next test?
The app is frozen. What easy safe test comes first?
For a grown-up
Let your child suggest the test. You do anything with plugs, batteries or updates.
Ask after each test: did that change anything? One at a time is the lesson.
Safety first
A child never touches plugs, chargers, batteries or the case during a test.
If a test needs a plug or a password, that test belongs to a grown-up.
Rocket wants to know which change fixed the sound. How many changes should he make before checking?
WHY THIS EXERCISEOne change per check is the only way to know what actually worked.

Excellent! You know how to test like a technician. Tomorrow you will write down your fixes and learn when to ask for help.

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