OBD Guide

P25C9

Brake System Control Module B Requested MIL Illumination

P25C9 is an OBD-II diagnostic trouble code meaning: Brake System Control Module B Requested MIL Illumination. Common causes: malfunction of the brake control module, problems with wiring or connectors. Estimated repair cost: $56–222.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–222 (est.)

Symptoms

  • Malfunction indicator lamp (MIL) is on
  • There may be problems with the operation of ABS or ESP
  • There may be errors in other vehicle systems
  • In some cases, a decrease in braking efficiency may be observed.

Causes

  • Malfunction of the brake control module
  • Problems with wiring or connectors
  • ABS sensor malfunction
  • Software error in control module
  • Module power problems

How to Fix

  1. Conduct brake system diagnostics
  2. Check the condition of the wiring and connectors
  3. Test ABS sensors
  4. Update control module software
  5. If necessary, replace the brake control module

Related codes

Error P25C9 by Vehicle Brand

FAQ

What does the P25C9 code mean?

P25C9 is an OBD-II diagnostic trouble code that indicates: Brake System Control Module B Requested MIL Illumination

What causes a P25C9 error code?

The most common causes of P25C9 include: Malfunction of the brake control module; Problems with wiring or connectors; ABS sensor malfunction; Software error in control module.

How do I fix a P25C9 diagnostic trouble code?

To fix P25C9: Conduct brake system diagnostics. Check the condition of the wiring and connectors. Test ABS sensors. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P25C9?

Limited driving only, diagnose soon

How much does it cost to fix P25C9?

The estimated repair cost for P25C9 is $56–222. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat