8D D2: write a problem description that holds up

D2 is where the reviewer first checks whether you understood the complaint. A vague D2 such as “parts out of spec” forces guesswork in D4 and makes every later step harder to accept. A strong D2 states what is wrong, on which parts, how much, since when and how it was found, in terms anyone can measure. It describes the problem, not the cause. Formats differ by customer, so check their 8D template and supplier manual.

Start with a measurable defect statement

One or two sentences that name the part, the characteristic, the requirement, the actual value and the quantity. Compare:

• Weak: “Customer complained about bad housings.”
• Strong: “Housing P/N 4711 rev C: bore diameter measured 12.08–12.11 mm against a specification of 12.00 ± 0.05 mm on 46 of 500 parts from lot 2310-14, found at customer incoming inspection on 3 Oct.”

Use the customer’s own words for the symptom, then add your measurement. If you haven’t confirmed the defect on returned or retained parts yet, say so and give the date you will.

5W2H: the questions D2 should answer

• What: part number, revision, characteristic and the defect as measured.
• Where: where it was found (customer line, incoming, field) and where on the part.
• When: production dates or lots affected, and when it was detected.
• Who: who detected it, and which customer or plant is affected. Not who is to blame.
• Why it matters: the effect on the customer, such as line stop, fit issue or safety concern.
• How: how it was detected and how the defect presents.
• How many: quantities found, checked and suspect, with the trend if known.

5W2H fills the facts. The Is / Is-Not table then narrows them into clues.

The Is / Is-Not table

For each dimension, write where the problem is seen and where it could be seen but isn’t. The contrast is what points D4 to the cause. Illustrative example (fictional) for a cosmetic scratch on a painted panel:

The contrasts (left only, rack contact, since week 39, night shift, missed at final inspection) give D4 specific things to test, on both the occurrence and the escape side. See how to write a D4 root cause.

Strong D2 statements: illustrative examples from different sectors

These examples are fictional and only show the structure.

• Electronics: “Board P/N 88-200: open solder joint on U7 pin 3, 12 of 1,200 boards, date codes 2338–2339, found at customer ICT.”
• Aerospace: “Bracket P/N A-310: hole position 0.3 mm out of tolerance on 4 parts of one batch, found at customer first article inspection.”
• Medical device: “Tubing set: incomplete bond at connector found on 3 units in customer leak test, single lot, no reports from the field.”
• Food packaging: “Pouch seal width below 6 mm minimum on 9 of 400 sampled, line 2 only, one production day.”

Pre-send self-check for D2

• Could someone outside the team find a defective part from the D2 alone?
• Does it give the requirement and the measured value, with units?
• Are lots, dates and quantities stated, and do they match D3?
• Does every Is have an Is-Not beside it?
• Has the defect been confirmed on returned or retained parts, or is the confirmation date given?
• Is it free of causes, blame and solutions?

Update D2 if the investigation changes the picture, for example when more lots turn out to be affected. Note the revision so the reviewer can follow what changed and why, rather than finding a different quantity in D3 than in D2.

Common weak D2s

• Restating the complaint title with no measurement or quantity.
• Naming a cause in D2: “Defect caused by worn tool.” That belongs in D4, once proven.
• No Is-Not side, so nothing narrows the search.
• Missing lots, dates or traceability, so the D3 scope can’t be checked.
• Mixing several defects into one problem statement.
• Blame wording such as “operator mistake”, which reviewers often read as a weak start for D4.

A clear D2 makes a weak D4 easier to spot. If your causes feel thin, compare them with weak D4 root cause examples. The free printable 8D / D4 checklist (PDF) covers D1–D8.

FAQ

Should D2 mention the root cause?

No. D2 describes the problem as observed. Suspected causes belong in D4, where they are tested.

What if I can’t fill every 5W2H field?

Write “unknown, under investigation” and the action to find out. A visible gap reads better than a guess.

What does 8D Gate check?

It gives a pre-send readiness check on the 8D text: an Accept / Conditional / Reject advisory with missing evidence and questions. It isn’t a customer decision. The review tool is v0.1: it reviews English 8D reports, and the interface and report are in English. Templates are also available in German, Czech and Polish.

Free pre-send readiness check

Before the 8D goes out, run the text through the free supplier 8D readiness check.

Get the free 8D / D4 checklist

Keep the one-page version ready for the next complaint. It covers D1–D8 and goes deeper on containment, D4 root cause, and verification.