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 there's a problem with the part of the car that helps keep the engine oil clean. It's getting too much power, like a light bulb that's too bright.
The P118A code is triggered when the engine control module (ECM) detects a higher than expected voltage in the engine oil separator heating circuit.
The engine oil separator is a component that helps remove oil from the air in the engine's crankcase ventilation system. It has a heating element to prevent freezing in cold conditions. When the ECM detects that the voltage in this heating circuit is too high, it sets the P118A code.
• Check Engine Light illuminated
• Possible engine performance issues
• Poor fuel efficiency
• Faulty oil separator heater
• Wiring issues such as shorts or open circuits
• Faulty ECM
ECM: Engine Control Module, the computer that controls engine functions.
OBD-II: On-Board Diagnostics, a standardized system for vehicle diagnostics.
• Check for any other related codes.
• Inspect the wiring and connectors for damage.
• Test the oil separator heater for proper resistance.
• Repair or replace damaged wiring or connectors.
• Replace the oil separator heater if faulty.
• Replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $500
Moderate
• BMW 3 Series
• BMW 5 Series
• BMW X5
• Regular maintenance and inspection of the engine components.
• Ensure proper electrical connections.
• Avoid extreme temperature conditions without proper vehicle preparation.
Sensor Issue
• Do not ignore the Check Engine Light.
• Consult a professional mechanic if unsure.
• Regularly check vehicle for any unusual signs.
Check with the vehicle manufacturer for specific warranty coverage related to emissions and engine components.
This code is more common in colder climates where the oil separator heater is more likely to be activated.
Moderate – It should be addressed soon to avoid potential engine issues.
Driving with a Check Engine Light on may not be legal in some regions and could lead to further vehicle damage.
• Engine must be running.
• Cold ambient temperatures may be required to activate the heater.
The engine oil separator is typically located near the engine, often integrated into the crankcase ventilation system.
Q: Can I drive with a P118A code?
A: It's not recommended to drive for extended periods with this code as it may lead to further engine issues.
Q: How can I reset the P118A code?
A: You can reset the code using an OBD-II scanner, but it's important to fix the underlying issue first.
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