EV Motor & Controller Repair

Jerking & hesitation

A jerk or surge when you accelerate is rarely the motor itself — usually rotor-position, throttle-sensor or controller logic. We find the real cause.

throttle · position

Power loss & limp mode

The turtle / 'limited performance' light and clamped power. We read why the controller or BMS is de-rating — often a sensor or software fault, not a dead motor.

limp mode · de-rate

Controller / inverter repair

The inverter handles huge currents. Failed IGBTs/MOSFETs, a tired DC-link capacitor or firmware faults cause jerking, no drive or lost regen — repaired at board level.

IGBT · MOSFET · firmware

Motor replacement & rewind

Burnt or shorted windings, water-damaged motors and physical damage — rewind where viable, or a like-for-like motor replacement to OEM spec.

winding · rewind · swap

Hall / position sensor

A PMSM must know exact rotor angle. A faulty resolver or Hall sensor causes rough running, jerking, cut-outs or a complete no-drive — diagnosed and replaced.

resolver · Hall

Bearing & noise

A new or growing whine, hum or grind usually means worn motor bearings or the reduction gearbox. We isolate it before it damages the rotor.

bearing · gearbox

Regen braking faults

Lost one-pedal feel or a regen warning? Because regen runs through the motor and controller, we trace it across the controller, sensors and software.

regen · one-pedal

Overheating & derating

Progressive power loss on long drives or in summer points to motor/controller cooling — low coolant, a weak pump or blocked flow. Found and fixed.

cooling · thermal

No-drive diagnosis

Powers on but won't move in D or R. We check the controller, HV fuse, contactors, position sensor and the wiring between pack, controller and motor.

contactor · HV fuse