Overview
A failed scan has three possible culprits — the method, the phone, or the tag — and the fastest diagnosis is swapping each in turn. Meanwhile, remember the scan is never a blocker: the same machine opens from the Equipment list or Recent Equipment, so work continues while you sort the tag out.
1. Swap the method
Every GoTag carries its identity twice:
- QR failing (glare, dirt, wear, torn face) → tap the NFC chip — it sits under the label and routinely survives damage to the printed face.
- NFC failing → scan the QR — and retry NFC by moving the phone slowly across the tag rather than holding it still; NFC antenna position varies wildly between phone models.
One method working = the machine identified, job done; note the tag for eventual replacement if its other half is dead.
2. Swap the phone
A tag one phone can't read is often fine on the next — NFC sensitivity and camera quality differ. A second phone reading it fine makes it a phone quirk: check the first phone's camera permission (for QR in-app) and NFC setting (some Androids ship NFC off).
3. Then it's the tag
Both methods, two phones, still nothing — the tag is damaged. See Damaged or Unreadable GoTag for the replacement path (a Technician's guided flow, a few minutes). Meanwhile: browse to the machine in the app; a dead tag never stops an inspection.
Scan works, but lands somewhere unexpected
| What happened | It means | What to do |
|---|---|---|
| "Not found" page | The tag isn't installed against any machine | New stock or retired tag — a Technician installs or replaces it |
| Machine opens, but pre-start is "Unavailable" | Machine's group is outside your licences | Not a scan problem — see Licensing Operators |
| The public logbook opened, not the app | The link opened in the browser | Open the app and scan from its Start tab, or open the link with the app installed |
| The wrong machine opened | You read a neighbouring machine's tag | In tight parking, NFC's near-contact beats QR at range |
Environmental quick wins
- Glare — shade the QR with your hand.
- Dirt and mud — wipe the tag; the label is wipe-clean by design.
- Gloves — NFC doesn't care about gloves; QR needs only the camera pointed.
- Rain on the lens — wipe the phone camera, not just the tag.
Troubleshooting
| Symptom | First move |
|---|---|
| QR won't read | NFC tap; shade and wipe, then retry QR |
| NFC won't read | Slow sweep across the tag; check NFC is on; fall back to QR |
| Neither reads on this phone | Second phone — split phone from tag |
| Neither reads anywhere | Replace the tag; browse to the machine meanwhile |
| Scan lands oddly | See the landing-page table above |