What it means
The ECM detects a circuit low fault on the drive motor a temperature sensor b circuit. Reading cannot be used reliably for control.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Drive Motor A temperature sensor B supplies a signal used to protect and control the motor. This code sets when the module sees the sensor B circuit signal too low, which can result from a short to ground, a shorted sensor, or a poor connection.
Common causes
Most likely first.
- Signal wire shorted to ground
- Internal sensor short
- Connector pins corroded - high contact resistance
Symptoms
- EV/hybrid system warning light on
- Reduced motor power or torque
- Possible limp mode or vehicle shutdown
How to diagnose it
- Check freeze-frame and live data for Drive Motor A temperature sensor B; a reading pinned unusually low can help confirm the low-signal condition.
- Inspect sensor B's connector and harness for chafing, pin damage, corrosion, moisture, or wiring touching ground.
- Following the manufacturer's safe procedure, isolate the sensor B circuit and check for an unintended short to ground.
- Test sensor B and its connector terminals against the manufacturer's specifications to identify an internal short or excessive contact resistance.
- Repair the short or connection fault, clear the code, and confirm sensor B data returns to a plausible range.
Common fixes
- Repair a sensor B signal wire that is shorted to ground.
- Clean or replace corroded or damaged sensor B connector terminals.
- Replace Drive Motor A temperature sensor B if it is internally shorted.
- Clear the code and verify the low signal no longer returns.
Can I keep driving?
Avoid demanding driving because the module may limit motor power or enter limp mode when sensor B reads too low. If the vehicle shows a shutdown warning or loses substantial power, stop safely and arrange service; a false temperature signal can interfere with motor protection.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.