P2741: Two different checks can flag the cooler-out temperature signal

In this transmission implementation, P2741 evaluates the cooler-out temperature sensor through two consistency checks. One rejects an absolute filtered temperature gradient above 700°C per second. The other compares cooler-out, sump and engine-coolant temperatures after a long shutdown.

An abrupt signal jump is one route

The gradient route requires enough samples for a valid calculation and no electrical sensor fault. The table uses five temperature samples, five raw gradients and a 60 ms confirmation timer. A single displayed temperature does not reveal the rate-of-change evidence.

Cold-soak disagreement is another

The comparison route requires at least eight hours of valid propulsion-system off time, the engine stopped and a startup window from two to twenty seconds. Cooler-out must disagree with coolant by more than 15°C and with sump by more than 10°C, while sump stays within 7°C of coolant. That pattern helps identify which of the transmission readings is inconsistent.

Preserve the three temperatures and the actual off-time state before startup data disappears. A warm-running agreement cannot directly verify the cold-soak branch. These checks identify implausible sensor information, not proof of overheating or a universal instruction to replace the cooler-out sensor.

Document scope and source

2025 GM 25OBDG07A Part 2 documented monitor only; its application-matrix filename join is unresolved. No model, engine or universal calibration applicability is inferred. These figures explain the cited controller logic, not a vehicle-specific repair instruction. Match the vehicle’s service information before applying them.

GM physical PDF page 988, GM physical PDF page 989.