Active Brake System Fault
Indicates a fault in the active brake control system.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The engine computer sees a problem with the brake system that helps to control braking force, which can lead to reduced braking effectiveness.
What the computer is actually seeing
The brake control module detects abnormal voltage or signal from the brake sensor. It may see voltages outside the expected range (e.g., below 0.5V or above 4.5V) indicating a fault condition.
What a healthy reading looks like
Expected sensor voltage should be between 0.5V and 4.5V during operation.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check brake fluid level. Ensure it's within the specified range. Decision: If low, refill and test; if normal, proceed to step 2.
- 22. Inspect wiring and connectors from the brake pressure sensor to the control module for damage or corrosion. Decision: Repair any issues found, then test; if no issues, proceed to step 3.
- 33. Measure the voltage at the brake pressure sensor. Expected range is 0.5V to 4.5V. Decision: If out of range, replace the sensor; if within range, proceed to step 4.
- 44. Clear the fault code and test drive the vehicle. Decision: If code returns, replace the brake control module. If it doesn't return, the issue may be resolved.
Common causes
- Wiring issues in the brake system
- Faulty brake pressure sensor
- Bad connection at the brake control module
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
No, it can reduce braking effectiveness, making it unsafe.
Will this code come back after clearing?
It may come back if the underlying issue isn't fixed.
Why does this code sometimes pair with SPN 613?
SPN 613 can indicate a related sensor fault, often seen together due to similar wiring issues.
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