An implausible diagnostic value may reflect a tool interpretation, unsupported parameter or genuine circuit issue. Do not assume that every negative number is physically meaningful, or that it can be ignored because it looks strange.
Preserve labels and units
Record the parameter name, tool version and operating state. Ask the technician whether that data item is supported for the controller. Compare with the vehicle’s own warnings and relevant related readings rather than interpreting one isolated value.
If a second supported method is used, retain both results. Avoid writing configuration or resetting a BMS to correct an unexplained display. The diagnostic question is what the controller and tool are actually reporting, followed by the checks needed to establish whether the underlying system behaves abnormally.
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