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 the air going into your car's engine isn't getting enough power to work properly.
The P15E5 code is triggered when the Engine Control Module (ECM) detects that the voltage supplied to the charge air cooler coolant pump is below the expected range.
The charge air cooler coolant pump is responsible for circulating coolant to the intercooler, which cools the air entering the engine. If the ECM detects an undervoltage condition, it means that the pump is not receiving enough electrical power to function correctly, potentially affecting engine performance.
• Reduced engine performance
• Check engine light illuminated
• Engine overheating
• Faulty charge air cooler coolant pump
• Wiring issues or poor electrical connections
• Faulty ECM or control module
ECM: Engine Control Module
Intercooler: A device used to cool air compressed by the turbocharger or supercharger.
• Check for any blown fuses related to the coolant pump.
• Inspect wiring and connectors for damage or corrosion.
• Test the voltage supply to the coolant pump.
• Replace faulty charge air cooler coolant pump.
• Repair or replace damaged wiring or connectors.
• Update or replace the ECM if necessary.
• Multimeter
• OBD-II scanner
• Basic hand tools
$150 - $500
Moderate
• BMW 3 Series
• Audi A4
• Mercedes-Benz C-Class
• Regularly inspect electrical connections.
• Ensure coolant levels are maintained.
• Perform routine vehicle maintenance.
Engine Performance
• Avoid driving aggressively until the issue is resolved.
• Monitor engine temperature closely.
• Seek professional diagnosis if unsure.
Check your vehicle's warranty coverage for components like the coolant pump.
This code has been more prevalent in vehicles with turbocharged engines, where the charge air cooler is crucial for performance.
Moderate – It should be addressed soon to prevent potential engine damage.
Ignoring this issue could lead to engine overheating, which may cause further damage and pose safety risks.
• Engine at operating temperature
• Vehicle in a stationary position
The charge air cooler coolant pump is typically located near the intercooler and the radiator in the engine bay.
Q: Can I drive with a P15E5 code?
A: It's not recommended to drive for extended periods with this code, as it could lead to engine overheating.
Q: How do I reset the P15E5 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue persists, the code will reappear.
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