Diagnostic article Generic OBD-II
P0A06: Hybrid coolant-pump feedback disagrees during an on command
P0A06 is documented as an on-command coolant-pump feedback disagreement in the GM BAS hybrid summary.
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Documented application
2009 General Motors diagnostic parameter file 09OBDG08 Engine Diagnostics.pdf. Section-specific modules and calibrations; no per-code model or engine applicability 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.
The P0A06 row in GM's BAS hybrid section evaluates starter/generator-controller coolant-pump control feedback while the pump is commanded on. The controller compares an echo-back signal with its low-side-driver output. This is an electrical feedback check, not a direct measurement of coolant flow.
The source contains conflicting directional wording
The row's heading includes both low and high wording, and its fault description does not cleanly resolve that conflict. This article therefore does not assign a universal wire-voltage direction from the table. The supported distinction is the pump-on test and disagreement between commanded output and returned feedback.
The source requires four observations at 80-millisecond intervals, producing the stated 320-millisecond evaluation, while the module is awake. That repeated state comparison is more specific than hearing the pump operate once.
Confirm the exact circuit before testing
P0A07 is listed under a pump-off condition on the same page. Keeping the command state separate is useful even though the printed high/low labels require clarification.
Use the exact hybrid service procedure to establish the control circuit and correct interpretation. Do not improvise power feeds or probe hybrid power electronics. Verification should include completed control-feedback monitoring and the separate coolant-pump functional assessment required for the vehicle. A running pump or an erased code does not establish that its monitored command and feedback agree.
Source and applicability
2009 General Motors diagnostic parameter file 09OBDG08 Engine Diagnostics.pdf. Section-specific modules and calibrations; no per-code model or engine applicability established. This explanation describes the documented monitor, not a universal repair procedure.
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
Motor Electronics Coolant Pump A Control 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