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 that helps control how the car moves is getting too much electricity. It's like when you plug something into an outlet and it gets too much power.
The Vehicle Dynamics Control Module is receiving a higher voltage than expected, which can affect its operation.
The C1118 code is triggered when the Vehicle Dynamics Control Module detects a voltage level that is higher than the specified range for the power supply circuit 'A'. This can interfere with the module's ability to manage vehicle stability and traction control functions.
• Illuminated check engine light
• Vehicle stability control warning light on
• Loss of traction or stability control functions
• Faulty Vehicle Dynamics Control Module
• Wiring issues such as short circuits or open circuits
• Faulty power supply or alternator
Vehicle Dynamics Control Module: A computer that helps manage the car's stability and traction.
Over-voltage: When the electrical system receives more voltage than it is designed to handle.
• Check the voltage supply to the Vehicle Dynamics Control Module.
• Inspect wiring and connectors for damage or corrosion.
• Test the alternator output for over-voltage conditions.
• Repair or replace damaged wiring or connectors.
• Replace the Vehicle Dynamics Control Module if faulty.
• Replace or repair the alternator if it is causing over-voltage.
• Multimeter
• OBD-II scanner
• Basic hand tools
$200 - $600
Moderate
• Subaru Outback
• Subaru Forester
• Subaru Impreza
• Regularly check and maintain the electrical system.
• Ensure connectors and wiring are secure and undamaged.
• Monitor alternator output voltage periodically.
Electrical Circuit Issue
• Avoid hard braking or sharp turns until the issue is resolved.
• Drive cautiously and avoid high-speed maneuvers.
Check with your vehicle manufacturer for warranty coverage on electrical components.
This code has been associated with vehicles experiencing electrical issues due to alternator over-voltage.
Moderate – It should be addressed soon to ensure vehicle stability systems function correctly.
Driving with impaired vehicle dynamics control can increase the risk of accidents. Address the issue promptly.
• Vehicle at operating temperature
• Stable electrical load (no additional accessories running)
The Vehicle Dynamics Control Module is typically located under the dashboard or near the center console.
Q: Can I drive with a C1118 code?
A: It's possible to drive, but it's not recommended as your vehicle's stability and traction control systems may not function properly.
Q: How do I reset the C1118 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, the code should not return.
Pro · Four-system diagnostics
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