Code Definition

P0559 — Charging System Voltage Low

System: Powertrain  |  Type: Generic (OBD-II Standard)  |  Make: Generic

About P0559

P0559 is a generic (obd-ii standard) powertrain diagnostic trouble code. It belongs to the P-prefix family of codes, which covers engine, transmission, emissions, or fuel-system faults.

When P0559 is stored, the module has detected a signal or supply voltage lower than the expected operating range.

Scanning & clearing: A generic OBD-II scan tool will usually read and clear powertrain (P) codes. For live data, freeze-frame capture, and bi-directional tests you may need a more capable scan tool that supports the vehicle's ECM protocol.

Because P0559 is a generic OBD-II code, its base definition is shared across manufacturers. The specific diagnostic steps, reference values, and repair procedures can vary by vehicle, and the TaT Diagnostic Assistant includes verified procedures submitted by working technicians.

Code Information

This fault code indicates that the engine control module (ECM) has detected a lower than expected voltage from the vehicle's charging system. The charging system, primarily comprising the alternator and associated circuitry, is responsible for providing electrical power to the vehicle and charging the battery. A low voltage in the charging system suggests that the alternator is not generating sufficient voltage and current to meet the vehicle's electrical demands and to keep the battery adequately charged. This could lead to poor vehicle performance and potential electrical system failures.

Quick Facts