Some motor-control designs estimate movement from current ripple rather than a separate position sensor. A missing external sensor does not necessarily mean the controller runs without feedback information.
Interpreting the evidence
Identify the actual control design before searching for a nonexistent position-sensor fault. Compare movement, current and any available diagnostic count. If the mechanism loses position after repair, check the supported initialisation and the quality of the movement evidence.
Keep this evidence
Send the actuator reference and the circumstances in which position becomes incorrect.
Not every motor uses ripple-based estimation. The presence of current ripple alone does not prove that this is how the vehicle controls it.
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Technical background from Texas Instruments. The referenced design explains the principle; the vehicle-specific procedure determines the repair.
Related reading — A motor-driver fault latch can remain after the original event. Browse all vehicle-electronics diagnostic notes or return to the repair library.