Diagnostic article Generic OBD-II
P0D77: driver-temperature circuit-high has an unresolved boundary in this table
The GM P0D77 row identifies an extreme output-driver temperature report, but its printed fail and pass comparisons overlap at the boundary.
Read before applying this article
Documented application
GM 2015 15OBDG01 Hybrid Diagnostics, only the cited EACCM monitor and calibration. Per-code vehicle and engine applicability has not been established; these historical thresholds are not universal service specifications.
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.
P0D77 is the output-driver temperature-sensor circuit-high diagnostic for the electric A/C compressor in this GM table. The input is named IGBT temperature. The circuit-high label refers to the diagnostic channel, not a conclusion that the power electronics are physically overheating.
Preserve the source limitation
The printed failure comparison uses a temperature input equal to −40°C, while the pass comparison includes values at or above −40°C. Those expressions overlap at the boundary. This article does not convert that ambiguity into a definitive service pass/fail test; the applicable calibration information is needed to resolve it.
Other conditions are clear: the table requires outside air above −7°C, sufficient low-voltage supply, Accessory or Run/Crank state and a compressor speed request above zero for the failure evaluation. It counts 30 failed samples out of 60 at a 50-millisecond interval.
Diagnose the report in context
A technician should retain the driver-temperature value, ambient reading and speed request together. The source also records a controller-reset prerequisite before passing can be enabled after failure; that does not establish resetting as a repair.
Do not interpret the low reported temperature as proof that the assembly is physically cold or safe to touch. The table offers neither an internal sensor replacement procedure nor high-voltage access instructions. Verification must follow the matching professional compressor procedure with the uncertainty in the printed boundary explicitly retained.
Source and applicability
GM 2015 15OBDG01 Hybrid Diagnostics, only the cited EACCM monitor and calibration. Per-code vehicle and engine applicability has not been established; these historical thresholds are not universal service specifications.
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 Circuit High
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