OBD Guide

P1427

Brake System Vacuum Pump Activation Short To Positive

P1427 is an OBD-II diagnostic trouble code meaning: Brake System Vacuum Pump Activation Short To Positive. Common causes: broken or damaged wiring in the pump control circuit, short circuit to positive in the pump activation circuit. Estimated repair cost: $17–89.

Severity
🔴 High
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$17–89 (est.)

Symptoms

  • Check Engine Light Is On
  • Hard brake pedal
  • Reduced braking performance
  • Noise from a constantly running vacuum pump

Causes

  • Broken or damaged wiring in the pump control circuit
  • Short circuit to positive in the pump activation circuit
  • Vacuum pump relay malfunction
  • Problems in the control unit
  • Malfunction of the vacuum pump itself

How to Fix

  1. Check the integrity of the wiring to the vacuum pump
  2. Check vacuum pump relay
  3. Check the resistance and operation of the pump solenoid valve
  4. Diagnose the control unit for errors
  5. If necessary, replace the vacuum pump

Related codes

FAQ

What does the P1427 code mean?

P1427 is an OBD-II diagnostic trouble code that indicates: Brake System Vacuum Pump Activation Short To Positive

What causes a P1427 error code?

The most common causes of P1427 include: Broken or damaged wiring in the pump control circuit; Short circuit to positive in the pump activation circuit; Vacuum pump relay malfunction; Problems in the control unit.

How do I fix a P1427 diagnostic trouble code?

To fix P1427: Check the integrity of the wiring to the vacuum pump. Check vacuum pump relay. Check the resistance and operation of the pump solenoid valve. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P1427?

Do not drive — repair immediately

How much does it cost to fix P1427?

The estimated repair cost for P1427 is $17–89. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat