C0138 Code - Base Brake System Pressure Circuit/Sensor Low
Quick Answer
The Electronic Brake Control Module (EBCM) uses an input from 2 brake fluid pressure sensors to enhance ABS braking and vehicle stability if equipped. Common causes include Faulty Electronic Brake Control Module (EBCM), Electronic Brake Control Module (EBCM) harness is open or shorted, Electronic Brake Control Module (EBCM) 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
- C0138 indicates Base Brake System Pressure Circuit/Sensor Low.
- Common causes
- Common causes include Faulty Electronic Brake Control Module (EBCM), Electronic Brake Control Module (EBCM) harness is open or shorted, Electronic Brake Control Module (EBCM) 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 C0138 Description
What are the Possible Causes of the DTC C0138?
- Faulty Electronic Brake Control Module (EBCM)
- Electronic Brake Control Module (EBCM) harness is open or shorted
- Electronic Brake Control Module (EBCM) circuit poor electrical connection
How to Fix the DTC C0138?
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 C0138 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 C0138 code?
Need more information on how to fix the C0138 code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the C0138 code diagnosed by a professional: Find a repair shop in your area
Information for Specific Makes
- C0138 Buick — Base Brake System Pressure Circuit/Sensor Low
- C0138 Cadillac — Base Brake System Pressure Circuit/Sensor Low
- C0138 Chevrolet — Base Brake System Pressure Circuit/Sensor Low
- C0138 GMC — Base Brake System Pressure Circuit/Sensor Low
- C0138 Pontiac — Base Brake System Pressure Circuit/Sensor Low
- C0138 Saturn — Base Brake System Pressure Circuit/Sensor Low
Frequently Asked Questions about C0138 Code
What does the OBDII code C0138 mean?
C0138 indicates a problem with the base brake system pressure circuit or sensor, specifically signaling that the pressure is too low.
What are common symptoms associated with the C0138 code?
Symptoms may include a warning light on the dashboard, reduced braking efficiency, a spongy brake pedal, or a complete loss of brake pressure in severe cases.
What could cause the C0138 code to trigger?
Possible causes include a faulty brake pressure sensor, wiring issues, leaks in the brake system, or problems with the brake control module.
How can I diagnose the C0138 code?
Start by scanning the vehicle for trouble codes, inspecting the brake system for leaks, checking the brake pressure sensor and its wiring, and testing the brake control module.
Is it safe to drive with the C0138 code?
It is not safe to drive with this code as it indicates a potential issue with the brake system, which could lead to brake failure.
What repairs are typically needed for the C0138 code?
Repairs may involve replacing a faulty brake pressure sensor, fixing wiring or connector issues, or addressing any leaks in the brake system.
Can the C0138 code be cleared without fixing the issue?
While you can clear the code, if the underlying issue is not resolved, it will likely return, and the brake system may remain compromised.
How can I prevent the C0138 code from appearing in the future?
Regular maintenance of the braking system, including inspections for leaks and ensuring proper sensor function, can help prevent the C0138 code from occurring.
Will the C0138 code affect my vehicle's performance?
Yes, low brake pressure can significantly impact your vehicle's braking performance, making it potentially dangerous to drive.
Discuss the causes and fixes for C0138 OBDII Code
Code C0138 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.
