Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the pump that helps cool the car's electric parts. It's using too much power and has shut off to protect itself.
The P1A86 code indicates that the motor electronics coolant pump 'A' has been cut off due to an overcurrent condition, which means it's drawing more electrical current than it should.
The motor electronics coolant pump 'A' is responsible for circulating coolant to maintain the temperature of the motor electronics. An overcurrent condition can occur when the pump is blocked, malfunctioning, or the electrical circuit has a fault, causing the system to shut down the pump to prevent damage.
• Check engine light on
• Overheating of motor electronics
• Reduced vehicle performance
• Blocked coolant passages
• Faulty coolant pump
• Electrical short circuit
Coolant: A fluid that absorbs heat and helps keep the engine from overheating.
Overcurrent: A condition where too much electrical current flows through a circuit.
• Check for any blockages in the coolant system.
• Test the electrical circuit for shorts or faults.
• Inspect the coolant pump for proper operation.
• Clear any blockages in the coolant passages.
• Replace the faulty coolant pump.
• Repair or replace any damaged wiring or connectors.
• Multimeter
• Coolant system pressure tester
• Wrench set
$200 - $600
Moderate
• Chevrolet Volt
• Nissan Leaf
• Toyota Prius
• Regular maintenance of the cooling system
• Check coolant levels frequently
• Inspect electrical connections periodically
Electrical Circuit Issue
• Avoid driving the vehicle until repaired to prevent further damage.
• Consult a professional mechanic for a thorough inspection.
Check with the vehicle manufacturer for warranty coverage on cooling system components.
This code has been more common in hybrid and electric vehicles due to their reliance on electronic cooling systems.
High – This issue can lead to overheating and damage to the motor electronics if not addressed promptly.
Driving with this issue may lead to vehicle breakdown or damage, which could be unsafe.
• Vehicle at operating temperature
• Coolant system under pressure
The motor electronics coolant pump is typically located near the engine bay, connected to the coolant lines.
Q: Can I drive with a P1A86 code?
A: It's not recommended to drive with this code as it can lead to overheating and damage.
Q: How do I know if my coolant pump is bad?
A: Symptoms include overheating, coolant leaks, and unusual noises from the pump area.
Pro · Four-system diagnostics
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Universal · Torque wrench
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Universal · Drive-on ramps
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