P2033: EGT sensor 2 high-range fault needs sensor-type confirmation

The GM system label for P2033 identifies exhaust-gas temperature sensor 2 out of range high. The table covers analog and digital thermocouple versions, but the digital malfunction cell unexpectedly says EGT 1. That wording conflict must be resolved before using the row to select a physical probe.

The supported comparison

For the analog version, the listed high boundary is resistance above 100,000,000 ohms. For the digital version, the printed reported-temperature boundary is above 1,289.85°C. These are raw-value plausibility criteria, not a declaration that the exhaust actually achieved the displayed extreme.

The source says the analog check addresses electrical failure of the temperature sensor and the digital check can identify module-to-probe wiring issues. Knowing which architecture is installed therefore changes which kind of evidence is relevant. Neither threshold alone locates the defective component.

Conditions for a valid result

The monitor must be enabled, cranking must be inactive and supply voltage in range. Run/Crank must be active, diagnostic reset and lost-communication errors absent, and the sensor initialization delay complete. Qualification uses 19 failing samples within 25 on a 100-millisecond task. Unlike the low-range row, the listed reporting class is Type A, one trip.

Verification requires a valid initialized signal and completed high-range test. Confirm the channel assignment through vehicle-specific service information before any probe-specific work. This article describes the 2025 GM monitor but retains its sensor-number inconsistency as an unresolved source limitation.

Source: GM monitor, PDF page 1390.