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 computer in the car that controls an alternative fuel system is having trouble remembering important information when the car is turned off.
The P0618 code indicates that the Keep Alive Memory (KAM) in the Alternative Fuel Control Module is experiencing an error. This memory is used to store data when the vehicle is turned off, and an error suggests a problem with data retention.
The Alternative Fuel Control Module (AFCM) manages the vehicle's alternative fuel system. The Keep Alive Memory (KAM) is a non-volatile memory that stores adaptive data and learned values. A P0618 code is set when the AFCM detects an issue with the KAM, indicating potential problems with data storage or retrieval.
• Check Engine Light is on
• Poor fuel economy
• Vehicle may run rough or stall
• Faulty Alternative Fuel Control Module
• Poor electrical connection
• Dead or weak vehicle battery
KAM: Keep Alive Memory
AFCM: Alternative Fuel Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the battery and charging system.
• Check the wiring and connections to the AFCM.
• Replace or repair faulty wiring or connections.
• Replace the Alternative Fuel Control Module if necessary.
• Ensure the battery and charging system are functioning properly.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $600
Moderate
• Ford F-150 CNG
• Chevrolet Silverado CNG
• Honda Civic Natural Gas
• Regularly check battery health.
• Ensure all electrical connections are secure.
• Perform regular vehicle maintenance.
Control Module Error
• Have the vehicle checked by a professional if the Check Engine Light comes on.
• Avoid using alternative fuel if the vehicle is not running smoothly.
Check with the vehicle manufacturer for warranty coverage on control modules.
This code is more common in vehicles with alternative fuel systems due to the complexity of managing multiple fuel types.
Moderate – It is advisable to address this issue soon to avoid potential drivability problems.
Driving with a malfunctioning control module may affect vehicle emissions and performance.
• Vehicle must be turned off and on to test KAM retention.
• Ensure battery voltage is within normal range.
The Alternative Fuel Control Module is typically located in the engine compartment or near the fuel system components.
Q: Can I drive with a P0618 code?
A: It's possible, but not recommended as it may affect vehicle performance and fuel economy.
Q: How do I reset the KAM?
A: Disconnect the vehicle battery for a few minutes to reset the KAM, but this may not fix the underlying issue.
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