Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the part of the car that controls how much air goes into the left rear wheel's braking system.
The C0018 code is triggered when the vehicle's computer detects a fault in the control of the air or fluid inlet for the left rear brake system.
The C0018 code indicates an issue with the left rear inlet control, which is part of the vehicle's braking system. This could involve the control valve or actuator responsible for managing the air or brake fluid flow to the left rear brake. The system may not be able to properly regulate the pressure, affecting braking performance.
• ABS warning light on
• Reduced braking performance
• Unusual noises from the rear brakes
• Faulty inlet control valve
• Damaged wiring or connectors
• Malfunctioning ABS module
ABS: Anti-lock Braking System
OBD-II: On-Board Diagnostics, Second Generation
• Inspect the wiring and connectors for damage.
• Check the functionality of the inlet control valve.
• Test the ABS module for errors.
• Replace damaged wiring or connectors.
• Replace or repair the inlet control valve.
• Reprogram or replace the ABS module if necessary.
• OBD-II scanner
• Multimeter
• Brake system pressure tester
$150 - $500
Moderate
• Ford Explorer
• Chevrolet Tahoe
• Toyota Highlander
• Regular brake system maintenance
• Routine inspection of brake lines and connectors
• Timely replacement of worn-out brake components
Brake System Issue
• Have the brakes inspected by a professional.
• Avoid driving at high speeds until the issue is resolved.
Check with the vehicle manufacturer for warranty coverage on brake system components.
The C0018 code has been associated with issues in vehicles equipped with advanced braking systems, particularly those with ABS.
High – Brake issues can significantly affect vehicle safety and should be addressed promptly.
Driving with a malfunctioning brake system can be dangerous. It is recommended to have the vehicle inspected and repaired by a certified technician.
• Vehicle parked on a level surface
• Engine off and cooled
The left rear inlet control is located near the left rear wheel, usually integrated into the brake assembly or ABS module.
Q: Can I drive with a C0018 code?
A: It's not recommended to drive with this code active, as it may affect braking performance.
Q: How do I reset the ABS warning light?
A: Fix the underlying issue first, then use an OBD-II scanner to clear the code.
Pro · Four-system diagnostics
A handheld scanner aimed at engine, transmission, ABS, and airbag diagnostic work.
Chassis and ABS faults usually need a scanner that can read brake-system data directly.
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Universal · Torque wrench
Useful when reassembly torque matters for wheel, suspension, and under-hood fasteners.
Useful when wheel, hub, or suspension hardware needs correct reassembly torque.
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Universal · Drive-on ramps
Helpful for safer access underneath the vehicle during exhaust, EVAP, and underbody inspection work.
Helpful for safer access during underbody inspection work.
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