Diagnostic article Generic OBD-II
P0B57: Block-six circuit high evaluates one upper signal limit
Read the GM P0B57 monitor and distinguish it from block-six paired low and rationality checks.
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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.
P0B57 is the high-limit monitor for block-six voltage sensing in this GM battery controller. The documented failure quantity is a block-six indication above 23V. The high-limit row does not require block seven to share the same high indication.
Related codes use different input combinations
P0B56 checks blocks six and seven together for low readings. P0B55 uses two scaled comparisons with pack voltage. P0B57 instead evaluates block six's upper signal limit, so those neighboring conditions should not be imported into its definition.
Run mode, an acceptable low-voltage supply and absence of the controller-performance fault are prerequisites. The failing-sample decision is 15 within 20 at 100ms intervals. This gives a more precise interpretation than calling any momentary high value a completed monitor failure.
Retain the exact channel and reference
Capture block-six voltage, its status and the independent pack voltage with companion sensing codes. An aggregate maximum-block display may not preserve which channel generated the event, and the block number alone does not locate a physical module in every pack.
The source supplies no diagnosis of overcharging, internal battery damage or a specific failed sensor component. A qualified high-voltage technician must use the correct service procedure and sensing diagram. Physical pack access requires prescribed isolation and verification; the calibration limit is not a charging target or a safe live-measurement instruction.
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 225.
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 F 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