Diagnostic article Generic OBD-II
P0AC1: The battery-current circuit-low label corresponds to positive range limits here
Read the GM P0AC1 three-range current criterion and preserve the document’s discharge-current sign convention.
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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.
P0AC1 is labeled battery-current sensor circuit low, but the GM table expresses its failure using positive current values. It explicitly defines battery discharge as positive. The electrical code label must therefore not be translated into “too little battery current.”
Three sensing ranges qualify together
The failure combination requires high-range current above 200A, middle-range current above 52A and low-range current above 22A. The conditions are joined by AND. A high value in only one displayed range does not reproduce the complete documented criterion.
The controller must be in run mode, with suitable low-voltage supply and the listed supply/controller faults absent. Its decision uses 30 failing samples out of 40 at 100ms intervals.
Keep the sign and range names
Save the three range values without discarding their signs or relabeling them as interchangeable measurements. A scan tool exposing only one combined current parameter may not show the individual inputs used by this diagnostic.
The table describes an out-of-range sensing condition; it does not prove a specific current sensor failed or establish a universal discharge-current limit for all hybrids. Diagnosis requires the matching battery-controller procedure. Physical work on the pack or high-current conductors must be handled by trained personnel using prescribed high-voltage isolation, rather than an improvised external-current test based on these calibration values.
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 234.
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 Pack Current Sensor A 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