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 pump that helps cool down the electronics in a hybrid or electric car is not spinning fast enough.
The P2C66 code indicates that the electronic control module (ECM) has detected that the coolant pump responsible for cooling hybrid or electric vehicle electronics is operating below the expected speed.
In hybrid and electric vehicles, electronics require cooling to maintain optimal performance. The coolant pump circulates coolant to dissipate heat from these components. If the pump operates below the expected speed, it may lead to overheating and potential damage to electronic components.
• Warning light on the dashboard
• Overheating of electronic components
• Reduced vehicle performance
• Faulty coolant pump
• Electrical issues such as a bad connection or wiring problem
• Failed pump control module
ECM: Electronic Control Module
Coolant Pump: A device that circulates coolant to dissipate heat from vehicle components.
• Check for any stored trouble codes and clear them.
• Inspect the coolant pump wiring and connections.
• Test the coolant pump for proper operation.
• Replace the faulty coolant pump.
• Repair or replace damaged wiring or connectors.
• Replace the pump control module if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$200 - $600
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regular maintenance checks on the cooling system.
• Ensure proper coolant levels.
• Inspect electrical connections periodically.
Cooling System Performance
• Avoid driving the vehicle if the electronics are overheating.
• Get the vehicle inspected by a professional mechanic.
Check with the vehicle manufacturer for warranty coverage on hybrid/EV components.
This code has become more common with the increase in hybrid and electric vehicles, highlighting the importance of maintaining cooling systems.
Moderate – Addressing this issue promptly can prevent damage to electronic components.
Operating a vehicle with overheating electronics can lead to safety risks and potential legal issues if it results in a breakdown.
• Vehicle at operating temperature
• Coolant levels checked
The electronics coolant pump is typically located near the battery pack or electronic control modules within the vehicle.
Q: Can I drive my car with a P2C66 code?
A: It's not recommended as it may lead to overheating and damage to electronic components.
Q: How do I know if my coolant pump is failing?
A: Signs include warning lights, overheating, and unusual noises from the pump area.
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