P0C34: Sensor F performance uses the other module groups

P0C34 is the battery-temperature sensor F performance comparison in this GM monitor. The controller asks whether the F report differs excessively from the average temperature reported by other module groups. It is a relative consistency test, not an absolute battery-overheat diagnosis.

Read the absolute difference

The documented boundary is a difference greater than 20°C. A report on either side of the average can meet that condition. Calling the fault simply “too hot” would discard the possibility of an unusually low reported value.

GM qualifies the result with 50 failures out of 67 samples, evaluated every 100 milliseconds. The controller therefore observes repeated disagreement. One scanner value recorded during a transient does not establish the complete qualifying sequence.

Preserve the reference validity

The temperature-rationality fault bundle must be false. This requirement belongs to the test's eligibility, so the relevant companion fault status should be retained with the individual and reference temperatures. A non-returning code while the comparison is blocked is not a completed verification.

A technician must determine whether the temperature difference is real or arises in the measurement path using the correct battery-specific procedure. The table does not identify a universal physical sensor location for F or mandate replacing a battery module. High-voltage access and thermal-system investigation require the applicable professional precautions, while the original code and temperature pattern remain the starting evidence.

Source and applicability

15OBDG01 Hybrid Diagnostics, cited controller and monitor only. Historical calibration limits are not universal specifications; per-code vehicle, engine and hardware applicability must be verified.

GM source, physical page 586.