Diagnostic article Generic OBD-II
P0D76: compressor driver temperature is checked against ambient and intake air
GM P0D76 uses a two-reference temperature comparison after an extended compressor-off period, with different deviation limits for each reference.
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Documented application
GM 2015 15OBDG01 Hybrid Diagnostics, cited HCP2/VICM output-driver temperature comparison only. No universal compressor thermal limit or model applicability is asserted.
The code alone does not identify a failed part or establish that a vehicle is safe to drive. Confirm the vehicle, reporting module and applicable service procedure.
P0D76 evaluates the electric-compressor output-driver temperature report, identified as IGBT temperature in this GM example. It is a plausibility comparison after a long off period, rather than a direct declaration that the inverter has overheated during operation.
The two reference limits are different
GM requires the IGBT temperature to differ from raw outside-air temperature by more than 15°C and from intake-air temperature by more than 10°C. Both discrepancies are required. The failure counter needs 35 failed samples out of 40 at a 100-millisecond interval.
The compressor must have been off for more than six hours. The specified temperature signals, supply voltage, power mode and coolant-to-ambient relationship must meet their enabling conditions. Ignoring that off-time requirement would turn a controlled comparison into an inappropriate test of a recently running compressor.
Use the whole temperature picture
Retain the driver, intake-air and ambient readings together with elapsed off time. If a reference-sensor fault is present, its status changes whether the comparison can support a conclusion about the driver-temperature report.
The different 15°C and 10°C limits should not be collapsed into one universal allowable difference. Nor does the code alone identify which of the measurements is inaccurate. The source provides monitor logic without a repair or access procedure. Qualified diagnosis must use the correct vehicle information and account for the high-voltage and refrigerant hazards of the electric-compressor assembly.
Source and applicability
GM 2015 15OBDG01 Hybrid Diagnostics, cited HCP2/VICM output-driver temperature comparison only. No universal compressor thermal limit or model applicability is asserted.
Article source documents
Source checks describe how the text was prepared; they do not certify a diagnosis or confirm compatibility with every vehicle using this code.
Original code reference
Dictionary definition
A/C Compressor Control Module Output Driver Temperature Sensor Performance
This definition retains its original catalog scope. The article above is limited to its explicitly documented application.
Reference scope
Generic OBD-II definition.
A manufacturer label does not establish the model, year, engine or module to which a diagnosis applies. Read the safety and diagnostic limits.
Definition source
- DTC Database: pinned community code definitions
Source checked · MIT