P04B0

What it means

The refueling vapor control valve - typically part of the ORVR or capless fueling system - has an open control circuit. The valve directs fuel vapor from the tank into the canister during refueling and must open when the fuel filler is opened. Without it, vapor escapes during refueling and the system fails leak diagnostics.

Is it safe to drive?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.

Most likely causes

• Open in harness or solenoid winding

  high

  One of the most commonly reported causes for this code — check this first.

• Pin pushed back out of connector body

  low

  Less common, but worth ruling out after the more likely causes.

• Cracked solder joint inside the module or sensor

  low

  Less common, but worth ruling out after the more likely causes.

Related help

• Full P04B0 diagnosis, causes & costs
• How to read check engine light codes
• Is it safe to drive with the light on?