ABS Motor Relay Performance
The C0109 code means the vehicle's onboard diagnostic system has detected: ABS Motor Relay Performance. This is a critical severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- moderate
- Estimated cost
- $50 - $300 (parts and labor)
Basic scanners cannot read ABS codes. BlueDriver reads all systems including ABS, SRS, and transmission through your phone.
Check Price on AmazonAffiliate link -- we earn a commission at no extra cost to you.
Basic scanners cannot read ABS codes. This one reads all four systems so you know exactly which sensor failed.
Check Price on AmazonAffiliate link -- we earn a commission at no extra cost to you.
Common Symptoms
- ABS warning light on
- ABS pump motor inoperative
- Traction control disabled
- No ABS pump sound at startup
Probable Causes (Ranked by Likelihood)
- Failed ABS motor relay Very High
- Corroded relay socket contacts High
- Damaged relay control wiring Moderate
- ABS module relay driver failure Low
Step-by-Step Diagnostic Procedure
-
Locate and inspect ABS motor relay
-
Swap relay with identical one to test
-
Check relay control circuit from ABS module
-
Test relay socket for corrosion
Frequently Asked Questions
What does code C0109 mean?
C0109 indicates a fault in the motor relay performance that affects ABS and related safety systems.
Can I drive with C0109?
You can drive short distances, but ABS and stability control may be affected.
How much does it cost to fix C0109?
Typical repair costs range from $50 - $300 including parts and labor.
Sources
This page is built from documented references. Verify against your own service info before repair work.
Explore More
Was this helpful?
Share carcodefinder.com with a friend who needs to decode their check engine light.