What this code means
A digital tachograph normally confirms vehicle motion from two independent sources: the mechanical motion sensor on the gearbox and, on smart tachographs, the GNSS signal or a second motion transducer. Code 80, motion conflict, means these two sources disagree — the manual describes it as a discrepancy in the evaluation of vehicle motion between the sensor and an independent signal source.
The manual names a typical case explicitly: the FERRY/TRAIN mode wasn’t set while the vehicle was being transported on a ferry or by rail. The motion sensor then registers no movement while GNSS detects a change of position — a conflict that has nothing to do with a technical fault.
What to do now
- Acknowledge the message on the display.
- Check ferry or train: if you are currently on a ferry or train and didn’t set FERRY/TRAIN mode, set it now from the menu, or at the next stop.
- If the message appears during normal driving (not on a ferry or train): you may continue driving, but print a daily printout and document manually from this point until the cause is confirmed.
- Consult an approved workshop as soon as possible — because of the possibility of tampering or a wiring fault.
Your tachograph logs this fault — TAGRA reads it
TAGRA doesn’t resolve a motion conflict — only an approved workshop can rule out tampering or fix a wiring fault. But once code 80 is written to the tachograph’s memory and your driver card, TAGRA finds it in your downloaded data, evaluates it and documents it — exactly what you need at a roadside check, and to show the fault was addressed.
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According to the manual, there are two core causes:
- The FERRY/TRAIN mode was not set while the vehicle was being transported on a ferry or by rail — the motion sensor reports standstill while GNSS registers a change of position.
- An actual discrepancy between the sensor and the independent source during normal driving — this can point to tampering (for example a magnet interfering with the sensor, or a swapped sensor) or faulty wiring.
Stoneridge, Actia and EFAS-4 log the same fault under practically identical wording, "vehicle motion data conflict", and classify it as critical too.
Can you keep driving?
Yes, in principle — unlike a security breach, code 80 does not automatically eject the card or stop the recording. But because of the critical classification and the possibility of tampering, the repair obligation under Article 37 of Regulation 165/2014 applies: a workshop visit as soon as circumstances permit. If the vehicle cannot return to base within a week of the breakdown or discovery of the fault, the repair must be carried out en route.
A motion conflict is stored in the vehicle unit’s mass memory and on the driver card, and shows up at every later evaluation or control. Enforcement officers treat repeated "vehicle motion data conflict" entries as a possible tampering indicator, which can trigger a closer inspection of the vehicle — even if the suspicion doesn’t hold up in the end. If the fault is left unrepaired, a roadside check can result in a violation for breaching the Article 37 repair obligation, regardless of whether tampering actually occurred.
Also displayed as
Drivers across Europe see the same fault under different on-screen wording. These are the real search terms used for code 80:
- Bewegungskonflikt 80 — German
- Konflikt ruchu 80 — Polish
- Bewegingsconflict 80 — Dutch
- Conflict de mișcare 80 — Romanian
- Conflitto di movimento 80 — Italian
Related codes
Frequently asked questions
Is motion conflict 80 always a sign of tampering?
No. By far the most common cause is that FERRY/TRAIN mode wasn’t set while the vehicle was transported on a ferry or by rail. But if the conflict occurs during normal driving, it can point to tampering or a wiring fault — which is why a workshop check is required in every case.
Can I keep driving with motion conflict 80?
Yes, in principle — the tachograph doesn’t eject the card or stop recording. Because of the critical classification, though, the repair obligation under Article 37 applies: a workshop visit as soon as circumstances permit. If the vehicle cannot return to base within a week of the fault, the repair must be carried out en route.
What is FERRY/TRAIN mode and how do I set it?
It tells the tachograph that the vehicle is moving without its own propulsion (on a ferry or by rail), so the motion sensor/GNSS discrepancy isn’t treated as a fault. It’s activated from the unit’s menu before the crossing starts and deactivated afterwards; check your tachograph model’s manual for the exact steps.
How does code 80 differ from a security breach?
A security breach — such as an opened housing — automatically ejects the driver card, even while driving, and is treated as the most critical case. With code 80 the card stays inserted and recording continues; the workshop requirement still applies because tampering can’t be ruled out.