Powertrain, generic (extended)

P2E2B Drive Motor A Excitation Current Too High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2E2B does not blame the sensor: the measured field current of drive motor A itself exceeds what the controller allows. In TI's example of an excitation stage, two switches and two diodes sit between the high-voltage rails; with both switches on, the rotor coil sees the entire DC-link voltage, and switches of this kind are rarely sized above about 50 A. A switch that sticks closed or a control loop that stops regulating therefore lets the current climb. Excess field current overheats the rotor coil, brushes and switches. The safe reaction TI describes is to command zero field current, which also removes rotor flux and back-EMF. No manufacturer documents P2E2B publicly. Sensor faults are P2E28 to P2E2A. The motor is usually shut down, so drive power from it is lost.

Likely causes

Excitation power switch shorted or stuck on
Field current control or gate driver fault in the inverter
Shorted turns in the rotor field winding

Symptoms

  • Electric drive warning lamp on
  • Sudden loss of drive power from motor A
  • Vehicle may not restart the drive system

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€300–6,000
Time1.5–8 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

drive motor a excitation circuitdrive motor ahybrid control module

Related codes

P2E28P2E29P2E2AP2E7BP0A78

References: ti.com, law.cornell.edu.