خرابی عایق سیم‌پیچ الکتروموتور

The enamel insulating an electric motor's windings failing, letting current leak between turns, between phases or to the motor's casing. Heat is what destroys it — every overheat event ages the enamel — so this is usually the end of a story whose earlier chapters were cooling problems, degraded transaxle fluid or sustained overload.

It is the genuine motor failure the phase-current codes exist to catch, and it announces itself asymmetrically: one phase drawing more current than its siblings, torque that judders at low speed, a growl where there was a hum. One measurement settles it — insulation resistance, phase to phase and phase to ground, taken with the high-voltage system safely isolated. That test is what separates a motor rewind or replacement from the cheaper answers (a damaged cable, a lying sensor, an inverter switch), and no motor or inverter should be condemned without it.

High-voltage work throughout: this diagnosis belongs to a hybrid-qualified workshop, never a driveway.