Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer has detected a problem with the electrical circuit that controls a pump used to cool the motor electronics. It's like if a fan in your computer stopped working because the wire connecting it was broken.
The P0B39 code indicates that the control circuit for the motor electronics coolant pump B is experiencing low voltage, which means the pump might not be working properly to keep the electronics cool.
The P0B39 code is triggered when the powertrain control module (PCM) detects a lower than expected voltage in the control circuit for the motor electronics coolant pump B. This could indicate an issue with the wiring, connectors, or the pump itself.
• Check Engine Light is on
• Overheating of motor electronics
• Reduced vehicle performance
• Faulty motor electronics coolant pump B
• Damaged or corroded wiring or connectors
• Faulty PCM or control module
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the coolant pump for proper operation.
• Replace or repair damaged wiring or connectors.
• Replace the motor electronics coolant pump B if faulty.
• Check and replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect wiring for damage.
• Ensure coolant levels are adequate.
• Perform regular maintenance checks.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have a professional diagnose the issue if unsure.
• Avoid driving the vehicle if overheating occurs.
Check your vehicle's warranty, as some components may be covered under emissions or powertrain warranties.
This code has been associated with hybrid and electric vehicles where cooling of motor electronics is critical.
High – This issue can lead to overheating and potential damage to the vehicle's electronics.
Driving with an overheating vehicle can lead to further damage and is not recommended. Ensure repairs are conducted by a qualified technician.
• Engine running
• Coolant pump operational
The motor electronics coolant pump is typically located near the vehicle's electric motor or battery pack.
Q: Can I drive with a P0B39 code?
A: It's not recommended to drive with this code active, as it can lead to overheating and damage to the vehicle's electronics.
Q: How can I reset the P0B39 code?
A: The code can be reset with an OBD-II scanner after the issue is fixed, but it will likely return if the underlying problem is not resolved.
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