Powertrain, generic · Hybrid propulsion

P0BF0 Drive Motor A Phase W Current Sensor Circuit High

Check engine lightOn

EmissionsRelevant

Drive cycleNot required

Limp modePossible

P0BF0 is the high-signal fault of the phase W current sensor in the motor A inverter. GM sets it above 700 A for 0.05 of 0.1 s in the 2016 tables or 0.1 of 0.15 s in a 2019 table, Type A, one trip; above 700 A, Type B, two trips, on the 2012 two-mode trucks; above 440 A, Type B, in the BAS Plus (eAssist) table; the 2011 Volt uses 800 A limits for this sensor family. A value this high without matching battery current points to the sensor, its supply or an open reference rather than to real overcurrent, which GM reports separately (P0C01). With P0BF0 active, GM's eAssist logic switches to sensorless current control and suspends P0BFD, so motor A is limited until repair.

Likely causes

Failed phase W current sensor inside the inverter

Sensor signal shorted to the sensor supply voltage or open reference ground

Poor contact at an internal or external inverter connector

Symptoms

Malfunction indicator lamp and hybrid warning
Reduced power from drive motor A

Repair estimate

DifficultyShop_onlyWorkshop job

Parts and labour€150–4,000

Time1–6 h

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

Parts involved

drive motor a phase w current sensorwiring harnesshybrid control module

References: gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com.