Powertrain, generic · Hybrid propulsion

P0BCC Generator Inverter Temperature Sensor A Circuit

Check engine lightOn

EmissionsRelevant

Drive cycleRequired

Limp modePossible

In a two-machine hybrid one inverter feeds the traction motor and a second one the generator, the machine that is mainly driven by the engine to charge the battery or start it. Its power switches carry thermistors so the controller can cut current before they overheat. P0BCC is the general circuit code for sensor A of that generator inverter, used for an electrical fault the controller does not classify as low, high or erratic. No manufacturer documents this exact code publicly; CARB requires hybrid components and their sensor inputs to be monitored for circuit faults. Without a valid reading the controller limits generator power, which can reduce charging and hybrid performance. The sensor normally sits inside the inverter assembly.

Likely causes

Fault of the sensor or its circuit inside the inverter assembly

Loose or corroded connector at the inverter

Software fault in the inverter or hybrid control module

Symptoms

Hybrid system warning or check engine lamp
Reduced generator output and battery charging
Engine runs more often or hybrid mode limited

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

generator inverter temp sensor awiring harnesshybrid control module

References: law.cornell.edu, gsi.ext.gm.com.