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 power supply to a pump that helps cool the car's motor electronics. It's like when a toy's battery is running low and it can't work properly.
The P1A87 code is triggered when the control module detects a low voltage condition in the supply circuit of the motor electronics coolant pump 'A'.
The motor electronics coolant pump is responsible for circulating coolant to maintain the temperature of the electronic components within the motor. A low supply voltage can indicate a problem with the electrical circuit, such as a poor connection, damaged wiring, or a failing pump.
• Check engine light on
• Overheating of electronic components
• Reduced vehicle performance
• Faulty coolant pump
• Damaged wiring or connectors
• Faulty control module
Coolant: A fluid used to prevent overheating by transferring heat away from the engine.
OBD-II: On-Board Diagnostics, a standardized system in vehicles for self-diagnosis and reporting.
• Inspect the coolant pump and wiring for damage.
• Check the voltage supply to the pump using a multimeter.
• Test the control module for proper operation.
• Replace the faulty coolant pump.
• Repair or replace damaged wiring or connectors.
• Replace the control module if necessary.
• Multimeter
• Screwdriver set
• OBD-II scanner
$200 - $600
Moderate
• Chevrolet Volt
• BMW i3
• Nissan Leaf
• Regularly inspect the cooling system.
• Ensure proper electrical connections.
• Perform routine maintenance checks.
Sensor Issue
• Do not ignore the check engine light.
• Seek professional diagnosis if unsure.
• Avoid driving the vehicle if overheating occurs.
Check with your vehicle manufacturer as some components may be covered under warranty.
This code is relatively common in hybrid and electric vehicles due to their reliance on electronic cooling systems.
High – If left unresolved, it can lead to overheating and damage to electronic components.
Driving with an overheating engine can be dangerous and cause further damage. It is recommended to address this issue promptly.
• Engine running
• Coolant system operational
The motor electronics coolant pump is typically located near the vehicle's electronic control modules, often within the engine compartment.
Q: Can I drive with a P1A87 code?
A: It's not recommended to drive with this code as it can lead to overheating and damage to electronic components.
Q: How do I reset the check engine light after fixing the issue?
A: You can reset the check engine light using an OBD-II scanner after confirming the issue is resolved.
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