OBD Guide

C1478

Front Left Wheel Brake Pressure Control Plausibility Failure

C1478 is an OBD-II diagnostic trouble code meaning: Front Left Wheel Brake Pressure Control Plausibility Failure. Common causes: malfunction of the pressure sensor in the left front circuit, abs module hydraulic valve problems. Estimated repair cost: $56–222.

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

Symptoms

  • ABS/ESP indicator is on
  • Deterioration of the stabilization system
  • Activating the emergency brake system

Causes

  • Malfunction of the pressure sensor in the left front circuit
  • ABS module hydraulic valve problems
  • Air in the brake system
  • Mechanical damage to brake lines
  • ABS module malfunction

How to Fix

  1. Diagnostics of the brake system with a scanner
  2. Checking the tightness of the left front wheel circuit
  3. Testing ABS module pressure sensors and valves
  4. Bleeding the brake system
  5. Replacing faulty components

Related codes

FAQ

What does the C1478 code mean?

C1478 is an OBD-II diagnostic trouble code that indicates: Front Left Wheel Brake Pressure Control Plausibility Failure

What causes a C1478 error code?

The most common causes of C1478 include: Malfunction of the pressure sensor in the left front circuit; ABS module hydraulic valve problems; Air in the brake system; Mechanical damage to brake lines.

How do I fix a C1478 diagnostic trouble code?

To fix C1478: Diagnostics of the brake system with a scanner. Checking the tightness of the left front wheel circuit. Testing ABS module pressure sensors and valves. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with C1478?

Limited driving only, diagnose soon

How much does it cost to fix C1478?

The estimated repair cost for C1478 is $56–222. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat