P082B: A low X-axis gear-lever signal means low duty cycle, not a gear position

P082B identifies the first gear-lever position sensor's X-axis circuit as low. In the cited GM implementation, the measured quantity is signal duty cycle. It is not a declaration that the lever is physically too low or that the transmission has selected a particular gear.

Read the signal representation correctly

The failure boundary is X-channel duty cycle below five percent. The controller must have been awake for at least 0.05 second before the monitor is eligible. Ten failed samples within twelve, evaluated on a 25-millisecond loop, produce the documented finding; reporting is two-trip.

A waveform's percentage is not interchangeable with its average voltage unless the applicable signal encoding has been established. The table provides no voltage conversion, connector terminal or physical lever-location map, so those details should not be inferred from the percentage.

Keep channel identity and wakeup timing

Preserve the raw X duty cycle for sensor 1, its diagnostic status and time since controller wakeup. An initial transition before the stated enable delay is not equivalent to repeated eligible low-duty observations.

A plausible decoded gear label also cannot replace the raw channel evidence used by this monitor. The source describes an electrical-range result; it does not distinguish a sensor fault from a connection or receiving-circuit problem. Use the matching selector-system procedure before making a hardware or gear-engagement conclusion.

Source and applicability

2025 GM 03B documented monitor only. Vehicle, engine and controller calibration applicability must be established separately; no model fitment is inferred from the file. GM PDF, physical page 607.