Fault Family System: Powertrain (P-Codes) 38 SAE Codes

Generator Phase Current Circuit

Diagnostic & Technical Explanation

Code P0A59 sets when the generator inverter's phase-current sensors report one of the three phases missing, out of balance, or exceeding the commanded value — evaluated against the generator's torque command rather than a propulsion torque request, since the generator's duty cycle is dominated by engine-start assist and charge blending. The most common physical causes are a corroded or loose phase-lead connection at the generator inverter, a damaged phase-current sensor, and a shorted or open generator winding turn. Because the generator sees repeated high-current transients during engine restarts, a phase fault here can also surface as a rough or failed engine-start event rather than a steady-state driving symptom.

These 38 diagnostic trouble codes share one detection mechanism and one repair path, which is why MechanicDB groups them into a single authored fault family rather than repeating the same explanation 38 times.

Codes in this family (38)

Code	Definition	Repair coverage
P0A59	Generator Current Sensor Circuit	3 ranked fixes
P0A5A	Generator Current Sensor Circuit Range/Performance	3 ranked fixes
P0A5B	Generator Current Sensor Circuit Low	3 ranked fixes
P0A5C	Generator Current Sensor Circuit High	3 ranked fixes
P0A6F	Generator Phase U Current	3 ranked fixes
P0A70	Generator Phase U Current Low	3 ranked fixes
P0A71	Generator Phase U Current High	3 ranked fixes
P0A72	Generator Phase V Current	3 ranked fixes
P0A73	Generator Phase V Current Low	3 ranked fixes
P0A74	Generator Phase V Current High	3 ranked fixes
P0A75	Generator Phase W Current	3 ranked fixes
P0A76	Generator Phase W Current Low	3 ranked fixes
P0A77	Generator Phase W Current High	3 ranked fixes
P0DFA	Generator Phase U-V-W Current Sensor Correlation	3 ranked fixes
P0E00	Generator Phase U Current Sensor Circuit	3 ranked fixes
P0E01	Generator Phase U Current Sensor Circuit Range/Performance	3 ranked fixes
P0E02	Generator Phase U Current Sensor Circuit Low	3 ranked fixes
P0E03	Generator Phase U Current Sensor Circuit High	3 ranked fixes
P0E04	Generator Phase V Current Sensor Circuit	3 ranked fixes
P0E05	Generator Phase V Current Sensor Circuit Range/Performance	3 ranked fixes
P0E06	Generator Phase V Current Sensor Circuit Low	3 ranked fixes
P0E07	Generator Phase V Current Sensor Circuit High	3 ranked fixes
P0E08	Generator Phase W Current Sensor Circuit	3 ranked fixes
P0E09	Generator Phase W Current Sensor Circuit Range/Performance	3 ranked fixes
P0E0A	Generator Phase W Current Sensor Circuit Low	3 ranked fixes
P0E0B	Generator Phase W Current Sensor Circuit High	3 ranked fixes
P0E0C	Generator Phase U-V-W Circuit/Open	3 ranked fixes
P0E0D	Generator Phase U-V-W Circuit Low	3 ranked fixes
P0E0E	Generator Phase U-V-W Circuit High	3 ranked fixes
P0ED4	Generator Phase X Current	3 ranked fixes
P0ED5	Generator Phase X Current Low	3 ranked fixes
P0ED6	Generator Phase X Current High	3 ranked fixes
P0ED7	Generator Phase Y Current	3 ranked fixes
P0ED8	Generator Phase Y Current Low	3 ranked fixes
P0ED9	Generator Phase Y Current High	3 ranked fixes
P0EDA	Generator Phase Z Current	3 ranked fixes
P0EDB	Generator Phase Z Current Low	3 ranked fixes
P0EDC	Generator Phase Z Current High	3 ranked fixes

What this page does not show

This page publishes the fault mechanism and the code index. The licensed dataset adds, for every one of the 15,886 codes, the full authored repair set (56,729 procedures in total) with the fields deliberately withheld here:

Procedures 2..n after the first-listed procedure
Aftermarket parts cost ranges in USD (est_parts_cost_min/max_usd)
Professional labor-hour estimates (est_labor_hours)
Step-by-step diagnostic and repair instructions
Replacement-part mappings and catalog lookups
6,637 manufacturer-specific OEM codes across 32 makes ($149 tier)

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