P0707: transmission range low voltage is encoded in PWM behavior

P0707 diagnoses a ground-short condition in internal transmission range-sensor circuit A in the cited TCM. The controller uses a pulse-width-modulated signal, so the code cannot be understood solely as a static selector-position disagreement.

Signal convention determines the threshold direction

For the table's direct PWM convention, duty cycle below 8.789 percent is the failure criterion. The row separately lists an inverse-voltage convention. Do not apply the direct-convention inequality before confirming the configured sensor and signal interpretation.

The detection design corresponds to less than 0.5 ohm between signal and controller ground. This is the circuit-fault specification behind the PWM decision, not a resistance measurement to perform on an energized transmission circuit.

Enable time matters

Battery voltage must exceed 9 volts for more than one second. The failure time must exceed half a second within a sample period exceeding 1.5 seconds, with a twenty-five-millisecond update. A quick selector movement or one low duty-cycle snapshot is therefore not the entire diagnostic result.

Record the configured sensor type, PWM interpretation and current range information together. This code does not identify a particular gear as mechanically failed or prove the range sensor assembly requires replacement. Verification should establish a passing enabled circuit monitor and correct range recognition using the exact transmission procedure. The source lists Type A over one trip but does not provide model or transmission-family applicability for an unidentified vehicle.

Source and applicability

Documented monitors in gm-2025-03a, model year 2025. These are module/calibration examples; vehicle, engine and transmission applicability must be confirmed independently. GM 2025-03a, page 1091.