Drive Motor Inverter Temperature Sensor Circuit High
The P0BD9 code indicates that the Powertrain Control Module (PCM) has detected a voltage signal from the drive motor inverter temperature sensor that is higher than the expected range. This sensor monitors the temperature of the inverter, which converts DC battery power to AC for the electric motor. A high circuit condition typically means the sensor signal is stuck at a high voltage, possibly due to a short to power, open ground, or a faulty sensor. This can lead to inaccurate temperature readings, potentially causing the inverter to overheat or the vehicle to limit power to protect components.
1. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced motor power or limp mode
- Overheating of the inverter or motor
- Poor electric vehicle range or performance
2. Most Common Causes
- Sensor 'D' signal circuit shorted to reference voltage (Vref) or battery power
- Open circuit or excessive resistance in the sensor signal wire
- Internal failure of drive motor inverter temperature sensor 'D'
- Corroded, oxidized, or bent pins in the sensor connector
- Faulty inverter control module or hybrid/electric vehicle control module
3. Step-by-Step Diagnosis
Step 1: Use a scan tool to retrieve all codes and freeze frame data.
Step 2: Visually inspect the inverter temperature sensor and its wiring for damage, corrosion, or loose connections.
Step 3: With the ignition off, disconnect the sensor and measure resistance; compare to manufacturer specs (typically 10k ohms at 25°C).
Step 4: Check for 5V reference voltage at the sensor connector with ignition on.
Step 5: If reference voltage is present and sensor resistance is out of spec, replace the sensor.
Step 6: If sensor is good, check for shorts to power or ground in the signal circuit; repair as needed.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive with this code, as it can cause the inverter to overheat and potentially damage the drive motor system. The vehicle may enter limp mode, reducing power and speed.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for parts and labor, depending on the vehicle and whether the sensor or wiring needs replacement.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.