C1118 Code - Trailer Brake Control Sensitivity Switch Circuit Malfunction
Quick Answer
The trailer brake control system has a control panel with the trailer gain and manual apply switches. Common causes include Faulty Trailer Brake Control Switch, Trailer Brake Control Switch harness is open or shorted, Trailer Brake Control Switch circuit poor electrical connection. 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 indicates Trailer Brake Control Sensitivity Switch Circuit Malfunction.
- Common causes
- Common causes include Faulty Trailer Brake Control Switch, Trailer Brake Control Switch harness is open or shorted, Trailer Brake Control Switch circuit poor electrical connection.
- 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.
Code C1118 Description
What are the Possible Causes of the DTC C1118?
- Faulty Trailer Brake Control Switch
- Trailer Brake Control Switch harness is open or shorted
- Trailer Brake Control Switch circuit poor electrical connection
- Faulty Chassis Control Module-Auxiliary
How to Fix the DTC C1118?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the C1118 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the C1118 code?
Need more information on how to fix the C1118 code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the C1118 code diagnosed by a professional: Find a repair shop in your area
Information for Specific Makes
- C1118 Buick — Trailer Brake Control Sensitivity Switch Circuit Malfunction
- C1118 Cadillac — Trailer Brake Control Sensitivity Switch Circuit Malfunction
- C1118 Chevrolet — Trailer Brake Control Sensitivity Switch Circuit Malfunction
- C1118 GMC — Trailer Brake Control Sensitivity Switch Circuit Malfunction
Frequently Asked Questions about C1118 Code
1. What are the common symptoms of OBDII code C1118 (Trailer Brake Control Sensitivity Switch Circuit Malfunction)?
- Common symptoms include issues with the trailer brake system, such as reduced sensitivity or complete failure of the trailer brakes.
2. What are the possible causes of OBDII code C1118?
- The code C1118 can be caused by a malfunction in the sensitivity switch circuit, a faulty trailer brake control module, damaged wiring, or poor electrical connections.
3. How can I diagnose OBDII code C1118?
- Diagnosing code C1118 involves inspecting the trailer brake control system, checking the sensitivity switch circuit for continuity, and using a scan tool to retrieve and analyze the code.
4. What should I do if I encounter OBDII code C1118?
- If you encounter code C1118, it is recommended to inspect the trailer brake control system, test the sensitivity switch circuit, and address any identified issues promptly to ensure safe trailer braking.
5. Can I still drive my vehicle with OBDII code C1118?
- It is not recommended to drive your vehicle with code C1118, as it can compromise the functionality of the trailer brake system, potentially leading to unsafe towing conditions.
6. How can I repair OBDII code C1118?
- Repairing code C1118 involves fixing the root cause of the issue, such as replacing a faulty trailer brake control module, repairing damaged wiring, or addressing poor electrical connections.
7. Is OBDII code C1118 a serious issue?
- OBDII code C1118 should be taken seriously, as it indicates a malfunction in the trailer brake control sensitivity switch circuit, which can impact the braking performance of the trailer.
8. Can OBDII code C1118 be reset without repairing the underlying issue?
- While you can clear the code temporarily, it is crucial to address the underlying problem causing code C1118 to prevent recurring issues with the trailer brake system.
9. How much does it typically cost to repair OBDII code C1118?
- The cost of repairing code C1118 can vary depending on the root cause of the issue, but it may involve parts replacement, wiring repairs, or sensor adjustments, potentially ranging from a few hundred to a thousand dollars.
10. Are there any preventive measures to avoid encountering OBDII code C1118 in the future?
- To prevent OBDII code C1118, regular maintenance of the trailer brake system, including inspecting wiring, connectors, and brake control components, can help identify and address potential issues before they trigger the code.
Discuss the causes and fixes for C1118 OBDII Code
Code C1118 comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
