Drive Motor Inverter Temperature Sensor B Circuit malfunction
What it means
The hybrid control system reports a problem in the circuit of drive motor inverter temperature sensor B. The inverter converts battery power for the drive motor and gets hot, so the module watches its temperature to avoid damage. Several codes share this stored name, so the exact fault subtype (signal low, high, erratic or missing) is not visible here.
Can I keep driving? Usually yes in the short term, but the car may limit power to protect the inverter, so get it read soon.
What this part does
The drive motor inverter temperature sensor measures how hot the inverter's power electronics are while driving the electric motor. The control module uses it to run cooling and to reduce power before the electronics overheat. Work on high-voltage parts is for trained people only. When it fails, you may notice limited power, a warning light, or an overheating message.
Common symptoms
What you'll notice
- Hybrid or check-engine warning light on
- Reduced power or limp mode
- Inverter or motor cooling fan running harder
- Hybrid system may shut down when hot
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Common causes
Most likely first
- Wiring or connector fault at the inverter temperature sensor
- Faulty temperature sensor inside the inverter
- Low inverter coolant or a weak coolant pump, if the temperature is truly high
- Inverter or hybrid control module fault
Repair
Likely repair
- Parts often involved: inverter (power electronics), hybrid/EV control unit, wiring or connector
- Labor: 1–6 h
- Difficulty: Hard
- DIY: Garage only
How to diagnose & fix
Work through it in order
- Read all hybrid codes and note any coolant-pump or inverter codes.
- Check the inverter coolant level when the system is cold.
- Inspect the sensor connector and wiring for corrosion or damage.
- Compare the live inverter temperature with the motor and coolant temperatures on a cold start; they should be close.
- Do not open the battery pack or touch orange high-voltage cables; leave any high-voltage testing to a trained technician.
Related codes
About this page
Scan figures come only from diagnostic scans recorded through our own apps and tools. Cars are usually scanned because a symptom or warning light prompted it, so these figures describe our scan records, not how often a fault occurs in any make or model.
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