C1118 2018 GMC Sierra Code - Trailer Brake Control Sensitivity Switch Circuit Malfunction
Quick Answer
The C1118 code for a 2018 GMC Sierra specifically refers to a Trailer Brake Control Sensitivity Switch Circuit Malfunction. Common causes include Damaged or corroded wiring in the sensitivity switch circuit, Faulty sensitivity switch, Malfunctioning trailer brake control module. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- C1118 2018 GMC Sierra indicates Trailer Brake Control Sensitivity Switch Circuit Malfunction.
- Common causes
- Common causes include Damaged or corroded wiring in the sensitivity switch circuit, Faulty sensitivity switch, Malfunctioning trailer brake control module.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
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Code C1118 2018 GMC Sierra Description
The C1118 code for a 2018 GMC Sierra specifically refers to a Trailer Brake Control Sensitivity Switch Circuit Malfunction. This code indicates that there is a problem with the sensitivity switch circuit related to the trailer brake control system in the vehicle. The trailer brake control system is an essential component for towing trailers as it helps to regulate the braking force applied to the trailer. The sensitivity switch circuit is responsible for adjusting the sensitivity of the trailer brake control system, allowing for optimal braking performance based on the weight of the trailer being towed.
Common Causes of C1118 2018 GMC Sierra
- Damaged or corroded wiring in the sensitivity switch circuit
- Faulty sensitivity switch
- Malfunctioning trailer brake control module
- Loose or poor connections in the circuit
- Water or corrosion damage to the components of the trailer brake control system
Symptoms of C1118 2018 GMC Sierra
- Illumination of the trailer brake warning light on the dashboard
- Inconsistent or delayed response from the trailer brake control system
- Uneven braking performance while towing a trailer
- ABS system activation when braking with a trailer attached
- Diagnostic trouble code (DTC) C1118 stored in the vehicle's computer system
How to Fix C1118 2018 GMC Sierra
- Begin by conducting a thorough visual inspection of the sensitivity switch circuit, checking for any visible damage, corrosion, or loose connections.
- Test the sensitivity switch using a multimeter to determine if it is functioning correctly. Replace the switch if necessary.
- Check the wiring and connectors in the circuit for any signs of damage or corrosion. Repair or replace any faulty components as needed.
- Test the trailer brake control module to ensure it is operating properly. Replace the module if it is found to be faulty.
- Clear the diagnostic trouble code from the vehicle's computer system and test the trailer brake control system to verify that the issue has been resolved.
Cost to Fix C1118 2018 GMC Sierra
The cost of repairing a C1118 code for a Trailer Brake Control Sensitivity Switch Circuit Malfunction can vary depending on the specific cause of the issue and the labor rates at the auto repair shop. In general, the cost of parts for this repair could range from $50 to $200, with labor costs adding an additional $100 to $300. Overall, the total cost of addressing this issue could range from $150 to $500. It is important to note that these are rough estimates, and actual costs may vary based on the location, vehicle make and model, and the extent of the repairs needed. It is recommended to consult with a professional mechanic to get a more accurate cost estimate for this repair.
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Frequently Asked Questions about C1118 2018 GMC Sierra Code
1. What does the OBDII code C1118 mean on a 2018 GMC Sierra?
C1118 indicates a malfunction in the Trailer Brake Control Sensitivity Switch Circuit, which affects the proper operation of the trailer brake system.
2. What are the symptoms of a C1118 code on a 2018 GMC Sierra?
Common symptoms include the trailer brakes not functioning properly, a warning light on the dashboard, and possible error messages related to the trailer brake system.
3. What causes the C1118 code to appear on a 2018 GMC Sierra?
The most common causes include a faulty trailer brake control sensitivity switch, damaged wiring or connectors in the circuit, or a malfunctioning trailer brake control module.
4. Can I still drive my 2018 GMC Sierra with a C1118 code?
You can still drive the truck, but towing a trailer without properly functioning trailer brakes is unsafe and not recommended.
5. How do I diagnose the C1118 code on my GMC Sierra?
Start by visually inspecting the trailer brake control sensitivity switch, wiring, and connectors for damage. Use a multimeter to test for continuity and voltage in the circuit if necessary.
6. How do I fix a C1118 code on a 2018 GMC Sierra?
Repairs may involve replacing the trailer brake control sensitivity switch, repairing damaged wiring, or recalibrating or replacing the trailer brake control module.
7. Is the C1118 code specific to trailer brake issues?
Yes, this code specifically relates to a malfunction in the trailer brake control sensitivity switch circuit.
8. How much does it typically cost to fix a C1118 code on a 2018 GMC Sierra?
Repair costs can vary, but replacing the trailer brake control sensitivity switch or repairing wiring may cost between $100 and $300 depending on labor rates and parts availability.
9. Can a faulty trailer brake control module trigger a C1118 code?
Yes, a malfunctioning trailer brake control module can cause the C1118 code if it fails to communicate properly with the sensitivity switch.
10. Will clearing the C1118 code solve the issue permanently?
Clearing the code may temporarily remove the warning, but the underlying issue must be resolved to prevent the code from returning.
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