2026 Protocol: Diagnostic for sensor failures, GNSS discrepancies, and how to avoid fines for suspected tachograph tampering.
The motion sensor, technically known as the KITAS sensor, is the heart of your vehicle's data integrity. Located on the gearbox, it transmits encrypted pulses to the tachograph vehicle unit (VU) to record speed and distance traveled. In 2026 models, this sensor works in tandem with the GNSS (Satellite) signal to validate that the truck's position matches the recorded movement.
When the system detects a discrepancy between these two data points, the dreaded "Motion sensor failure" is triggered. To an inspector, this error is not just a technical breakdown; it is a red flag suggesting the use of magnets or signal interruption devices. Therefore, managing this error within the first few minutes is vital to avoid fines that can reach €4,001 under the 2026 sanctions scale.
Indicates the sensor has stopped receiving power. Before suspecting tampering, check the wiring coming up from the gearbox. It is common for friction against the chassis or accumulated dirt to cut the power supply.
This is the most dangerous error. It means the tachograph detects movement via GNSS but not via the KITAS sensor (or vice versa). If this occurs on the road, immediately perform a technical printout to justify the failure during a potential roadside stop.
If the sensor fails, the law is strict. You are obliged to act under the principle of good faith to avoid operator liability.
From the moment the error appears, the tachograph is no longer a reliable source of data. You must begin recording your driving activity, other work, and rest on the back of the tachograph thermal paper. Ensure you indicate the location, date, and reason for the failure.
European regulations grant a maximum period of 7 calendar days to take the vehicle to an authorized technical center. Driving beyond this period with an active error is considered a Very Serious infringement. Always keep the workshop appointment receipt as proof of due diligence in case of a roadside inspection.
Not every sensor error is a fraud attempt. Here are the most common technical causes we detect when analyzing .DDD files:
| ELEMENT | BREAKDOWN | ON-SCREEN SYMPTOM |
|---|---|---|
| KITAS Cable | Cut due to vibration or temperature | Constant communication failure |
| GNSS Antenna | Obstruction or module failure | Position error / Conflict 17 |
| Backup Battery | Internal accumulator depletion | Memory loss during power cuts |
| Interference | Unshielded electronic equipment | Sporadic sensor errors |
The best defense against a sensor error is the transparency of your data. If your tachograph records a fault, our software allows you to visualize exactly when it occurred and contrast it with your manual records. When filing an appeal or facing an inspection, having a technical report explaining the nature of the KITAS sensor failure is the difference between an ordinary repair and a catastrophic sanction for your company's good repute.
Suspect a real error? Analyze your .DDD to confirm there are no legal risks.
Next step
Get total control of your .DDD files and protect your good repute with TachoTools.