OBD Guide

P0499

EVAP System Vent Valve Control Circuit High

P0499 is an OBD-II diagnostic trouble code meaning: EVAP System Vent Valve Control Circuit High. Common causes: short circuit in the valve circuit to +12v, open circuit in valve control circuit. Estimated repair cost: $33–89.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$33–89 (est.)

Symptoms

  • Check Engine Light Is On
  • Poor engine performance at idle
  • Increased fuel consumption
  • Unstable engine operation

Causes

  • Short circuit in the valve circuit to +12V
  • Open circuit in valve control circuit
  • Purge solenoid valve malfunction
  • Problems in the wiring harness
  • Engine ECU malfunction

How to Fix

  1. Check the integrity of the wiring harness to the valve
  2. Measure the valve resistance (should be between 20-50 Ohms)
  3. Check the voltage at the valve connector with the ignition on
  4. Check the circuit for a short circuit to ground or +12V
  5. If necessary, replace the EVAP purge valve

Related codes

Error P0499 by Vehicle Brand

FAQ

What does the P0499 code mean?

P0499 is an OBD-II diagnostic trouble code that indicates: EVAP System Vent Valve Control Circuit High

What causes a P0499 error code?

The most common causes of P0499 include: Short circuit in the valve circuit to +12V; Open circuit in valve control circuit; Purge solenoid valve malfunction; Problems in the wiring harness.

How do I fix a P0499 diagnostic trouble code?

To fix P0499: Check the integrity of the wiring harness to the valve. Measure the valve resistance (should be between 20-50 Ohms). Check the voltage at the valve connector with the ignition on. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P0499?

Limited driving only, diagnose soon

How much does it cost to fix P0499?

The estimated repair cost for P0499 is $33–89. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat