OBD Guide

P1578

Brake Booster Vacuum Sensor Circuit Low Vacuum

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$17–56 (est.)

Symptoms

  • Increased brake pedal force
  • Deterioration in braking performance
  • Check Engine Light Is On
  • Unstable engine operation at idle
  • Noises when operating the brake booster

Causes

  • Brake booster vacuum sensor malfunction
  • Vacuum leak in the brake booster system
  • Open or short circuit in the sensor circuit
  • Vacuum pump malfunction
  • Problems with the sensor wiring harness

How to Fix

  1. Check the continuity of the brake booster vacuum sensor circuit
  2. Check for vacuum leaks in the system
  3. Test the brake booster vacuum sensor
  4. Replace the vacuum sensor if necessary
  5. Check and, if necessary, replace the vacuum pump

Related codes

Error P1578 by Vehicle Brand