U0418
Invalid Data Received From Brake System Control Module A
Communication network (brakes)
Generic OBD-II
Medium
What it means
U0418 sets when a control module reads data from the brake system control module that is missing, out of range, or implausible. Base braking usually remains, but ABS, stability control, and brake-assist features can shut off — and because some vehicles route braking assist through this module, it's worth checking promptly.
Medium
Can I keep driving? Base braking generally still works, but ABS, stability, and brake-assist features may be disabled — brake carefully and get it checked promptly.
Common symptoms
What you'll notice
- Brake, ABS, and stability warning lights on, usually with the check-engine light
- ABS and stability control disabled
- Reduced or changed brake-assist feel on some vehicles
- Normal (base) braking still available
- Related communication codes stored in other modules
Common causes
Most likely first
- Faulty brake system control module or its power/ground supplyLikely
- Corroded, loose, or damaged connectors and data-bus (CAN) wiringCommon
- Low or unstable battery and charging-system voltageCommon
- Software incompatibility after a module was replaced or updatedLess often
- An underlying brake-system sensor or actuator fault reported by the moduleLess often
How to diagnose & fix
Work through it in order
- Scan all modules and record stored codes and freeze-frame data before clearing.
- Check battery and charging voltage — low or noisy voltage is a common cause of bus faults.
- Inspect connectors and wiring to the brake system control module and along the data bus.
- If a module was recently replaced or flashed, confirm the software is compatible.
- Run the manufacturer's pinpoint tests on the brake system module and its inputs; replace only if confirmed.
FAQ
Quick answers
Is it safe to drive with U0418?+
Base brakes usually still work, so you can drive carefully, but ABS, stability, and any brake-assist features may be off — allow extra stopping distance and get it checked promptly, as some vehicles use this module for braking assist.
Can I just clear U0418?+
You can, but if the brake system module or its data link is still faulty the code returns and the brake/ABS warning lights come back on.
Related codes
Often seen with U0418
Read & clear U0418 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX