5 Whys template for finding the root cause
Updated · Reviewed by Israel Margulies, founder and CEO of High Point GPS
A 5 Whys template: write the problem, ask "why did that happen?" and write the answer, then ask why again, up to five times or until you reach a cause you can act on. Finish with the countermeasure, who owns it and when it's due.
The 5 Whys is the quickest root cause tool there is, and it works best on problems with one main chain of causes. A machine stopped because a hose burst; the hose burst because it rubbed through; it rubbed because a clamp was missing; the clamp was missing because the last repair didn't replace it; and the repair didn't because the procedure doesn't list it. Now you know what to fix.
Five is a guide, not a rule. Stop when the answer is something you can change, and back each answer with evidence rather than a guess. For failures with several causes, use a full root cause analysis instead.
5 Whys
Fields: Problem · Machine / asset · Date · Work order no. · Team
Log columns: Why? · Answer · Evidence
- Root cause. The cause that, if removed, would have prevented the problem.
- Countermeasure. What will change, who owns it and the due date.
Fill it in the right way
- Write the problem as a fact: what happened, on which machine, when.
- Ask why it happened and write the answer with the evidence for it.
- Ask why again about that answer, and keep going until you reach a cause you can act on.
- Write the root cause and a countermeasure, with an owner and a due date.
- Check later that the problem hasn't come back.
Tips
- Do it with the people who were there, at the machine if you can.
- If an answer is a guess, go and check before asking the next why.
- Stop at causes you can change; "the weather" isn't one, "no cover on the panel" is.
- If the chain splits, follow each branch or switch to a full RCA.
Do it in FleetZap
- FleetZap's work order history on each machine shows when the same problem happened before.
- Countermeasures can become a new step in the machine's PM checklist, so they're done every time.
FleetZap Maintenance
Work orders, PM, parts, compliance, assets and KPIs. Explore FleetZap Maintenance.
Frequently asked questions
What is the 5 Whys method?
A root cause technique where you ask why a problem happened, then why that happened, about five times, until you reach a cause you can fix.
Do you always ask exactly five whys?
No. Five is a rule of thumb. Stop when you reach a cause you can act on; some problems need three, some more than five.
When is 5 Whys not enough?
When a failure has several causes acting together. A full root cause analysis or a fishbone diagram suits those better.
Who should take part?
The operator, the technician and whoever knows the process, so each answer is based on what really happened.