A decoder needs a reliable way to distinguish high and low signal levels. Noise or an unsuitable threshold can create apparent data errors in an otherwise usable recording.

What to check next

Review the raw voltage trace first, including its high and low levels during the fault. Then check decoder threshold, hysteresis and time resolution. A diagnosis is stronger when the same suspected defect remains visible in the waveform instead of appearing only as a red entry in a decode table.

Useful information for an enquiry

Keep the original capture and note the probe range, sample settings and decoder configuration.

Changing settings until the table looks clean is not validation. Settings must match the actual interface and preserve evidence of genuine disturbances.

Speak to AXION

For complex vehicle-electronics diagnostics, send your vehicle details and fault report. Workshop assessment is in Didcot, Oxfordshire. Suitable postal or remote work is confirmed before booking.

Technical background from Pico Technology. The referenced design explains the principle; the vehicle-specific procedure determines the repair.

Related reading — A SENT signal is not an ordinary duty-cycle measurement. Browse all vehicle-electronics diagnostic notes or return to the repair library.