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 electric pump that helps cool the motor electronics. It's like a fan that stops working, so things can get too hot.
The P0B38 code indicates a malfunction in the control circuit of the secondary coolant pump for the motor electronics, which may be due to an open circuit or a control issue.
The Motor Electronics Coolant Pump B is responsible for circulating coolant to manage the temperature of the motor electronics. An open circuit or control failure in this pump can lead to inadequate cooling, potentially causing overheating and damage to electronic components.
• Check Engine Light on
• Overheating of motor electronics
• Reduced vehicle performance
• Faulty coolant pump
• Open or shorted wiring in the pump circuit
• Bad control module
Coolant: A fluid that absorbs heat and helps keep the engine at the right temperature.
Circuit: A path for electricity to flow through.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the coolant pump.
• Test the coolant pump for proper operation.
• Replace the faulty coolant pump.
• Repair or replace damaged wiring or connectors.
• Replace the control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Ford Fusion Hybrid
• Regular maintenance checks
• Ensure proper coolant levels
• Inspect wiring for wear and tear
Cooling System Issue
• Avoid driving the vehicle until repaired to prevent damage.
• Regularly check coolant levels.
Check with the manufacturer for warranty coverage on the cooling system components.
This code has been more prevalent in hybrid and electric vehicles due to their reliance on electronic cooling systems.
High – If not addressed, it can lead to overheating and damage to electronic components.
Driving with an overheating engine can lead to significant damage and may not be covered under warranty if ignored.
• Engine must be running.
• Vehicle should be at operating temperature.
The coolant pump is typically located near the motor electronics or in the engine bay.
Q: Can I drive with a P0B38 code?
A: It's not recommended as it can lead to overheating and damage.
Q: How do I reset the P0B38 code?
A: Fix the underlying issue first, then use an OBD-II scanner to clear the code.
Pro · Four-system diagnostics
A handheld scanner aimed at engine, transmission, ABS, and airbag diagnostic work.
Chassis and ABS faults usually need a scanner that can read brake-system data directly.
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Universal · Torque wrench
Useful when reassembly torque matters for wheel, suspension, and under-hood fasteners.
Useful when wheel, hub, or suspension hardware needs correct reassembly torque.
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Universal · Drive-on ramps
Helpful for safer access underneath the vehicle during exhaust, EVAP, and underbody inspection work.
Helpful for safer access during underbody inspection work.
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