Diagnostic article Generic OBD-II
P0BC5: Sensor E circuit high can look extremely cold
GM’s P0BC5 high-circuit threshold corresponds to a reported temperature below −40°C, so electrical direction and temperature must be separated.
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Documented application
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.
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.
P0BC5 names the high-circuit diagnostic for battery-temperature sensor E in this GM table. The electrical label does not mean that the battery is hot. Its explicit threshold pairs a reported temperature below −40°C with an ADC count above 3992.
Distinguish the signal from physical temperature
That extreme converted value can be a symptom of the sensing path. It is not independent confirmation that the battery has reached the displayed temperature. Preserve the signal report and the companion electrical faults before drawing a thermal conclusion.
The criterion must occupy 1.4 seconds of a two-second window, evaluated every 200 milliseconds. The pass row requires at least −40°C and an ADC count no greater than 3992 for two seconds. Failure and recovery therefore both involve qualification time.
Check the high-circuit prerequisites
The table excludes specified communication, 5-volt-reference and internal-performance faults, as well as the indicated bus-off condition. The secondary protection self-test must be inactive and communication enabled. Those conditions determine whether a retest can provide fresh evidence.
The strategy wording refers to temperature going above a threshold despite the explicit cold-temperature boundary. That discrepancy remains a source-review flag; no missing interpretation is presented as an OEM instruction. Sensor E's physical position and any high-voltage battery inspection require the actual vehicle service information and a suitably trained technician.
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 639 · GM source, physical page 640.
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
Hybrid/EV Battery Temperature Sensor E 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