P032D: high output from the documented knock-sensor 3 circuit

P032D identifies a high-circuit result for knock sensor 3 in the source, matching the catalog’s sensor C designation. The failure description is a short-to-battery pattern based on filtered sensor output.

What must exceed the limit

The table gives a filtered-output threshold above 4.7 volts with engine speed above 500 rpm. It requires three events and lists two-trip reporting. These events describe repeated qualifying results; the page does not make them equivalent to a fixed three-second delay.

Because the quantity is filtered, a single unfiltered voltage sample cannot be substituted without knowing the controller’s measurement method. Equally, a high diagnostic output is not a direct measurement of intense knock inside a cylinder.

Implications for diagnosis

Identify the exact sensor channel through the correct vehicle documentation before interpreting sensor C as a physical location. The recorded circuit-high result supports investigation of the signal’s electrical behavior, but it does not determine which component produced it.

Verification should confirm a completed high-circuit diagnostic at an enabled engine speed and preserve its event status. A brief return to a normal displayed value can be narrower evidence than the required sequence of passing observations. No sensor replacement, connector pin, or universal knock-sensor voltage test is established by this monitor summary.

Documentation and applicability

These details describe the monitor in GM’s 2025 25OBDG07A Part2 file. Its application-matrix filename does not match the download index, so model and engine applicability remain unresolved. Use the vehicle’s correct service information before applying these calibration details.

GM diagnostic table, PDF page 600.