P0712: transmission temperature circuit low means very low inferred resistance

P0712 is the low-voltage transmission-fluid temperature circuit diagnostic in the cited TCM. The controller converts its analog voltage assessment into a circuit-resistance value and detects the short-to-ground signature below 13.500 ohms.

Electrical low is not cold fluid

The code's low label refers to the electrical circuit. It is not a declaration that fluid temperature is below the acceptable operating range. Interpreting it as a warmup problem would confuse this electrical monitor with the separate performance checks.

The value in the table is an inferred circuit resistance used by the controller. It is not an instruction to place an ohmmeter across an energized sensor circuit. The exact vehicle wiring and test procedure are needed before physical measurement.

Persistence and supply conditions

Failure time must exceed five seconds within a sample window exceeding six seconds, updated once per second. Battery voltage and run/crank voltage must each exceed 9 volts for more than one tenth of a second. A brief low observation during an unqualified supply event is not the same as an enabled failure.

A useful record pairs raw temperature or circuit information with supply conditions and test status. Verification should demonstrate that the low-resistance signature is absent and the electrical monitor passes before using temperature data for further warmup diagnosis. The table specifies Type B over two trips but does not name a required sensor replacement, connector location or transmission-service operation.

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 1096.