Diagnostic article Generic OBD-II
P0B47: A low block-three report includes the block-four signal
Read the GM P0B47 low-sense criterion and preserve the two-channel evidence it requires.
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Documented application
GM 2010 10OBDG10 Hybrid Diagnostics, only the cited controller and monitor. These are historical calibration examples; individual vehicle, engine and hardware applicability is not established.
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.
P0B47 is the block-three voltage circuit-low monitor. In this GM table, failure requires both block three and block four to indicate less than 2V. The neighboring input is therefore part of the actual diagnostic criterion, not merely an optional comparison.
The controller qualifies a pair of low signals
The AND condition is evaluated with the battery controller in run mode, its low-voltage supply in range and P0A1F inactive. The monitor counts 15 failures within 20 samples at 100ms intervals.
A single low block-three value may warrant investigation, but it does not establish that the documented P0B47 sample sequence completed. Preserve whether block four was also low at the same time, rather than comparing readings captured at separate moments.
Do not mistake the pattern for a proven wiring fault
The two-channel requirement is supported by the source, but a particular shared-wire or connector explanation is not. The physical sensing arrangement must be established from the correct battery diagram. Nor does the code prove that two battery blocks have actually discharged below the limit.
Record companion high-limit and rationality codes before clearing the data. A qualified high-voltage technician should use the applicable circuit procedure to distinguish sensing faults from actual voltage conditions. Pack access requires approved isolation and verification; low scan values are not a substitute for proving a safe electrical state.
Source and applicability
GM 2010 10OBDG10 Hybrid Diagnostics, only the cited controller and monitor. These are historical calibration examples; individual vehicle, engine and hardware applicability is not established. GM PDF, page 223.
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 Voltage Sense C Circuit Low
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