OBD-II Code
P0447
Severity
Not yet reviewed
Nobody on our side has assessed this code yet, so we are not going to guess at how serious it is.
Can you drive it
We cannot say
Treat it as unknown until a shop reads it with live data. If the check-engine light is FLASHING, stop driving as soon as it is safe to — that means an active misfire, whatever the code.
Indicative cost (USD)
$50–$250
From this code's diagnostic notes. Varies by vehicle, diagnosis, parts, and local labor. This is not a repair quote.
P0447 means the ECM commanded the EVAP vent valve (also called canister vent solenoid or CVS) to close for a leak test but detected an open electrical circuit on the control side - either the solenoid coil is open, the wiring to the solenoid is broken, or the PCM driver itself has failed.
How a shop works this
Work from evidence to part, not the other way round. A code names a circuit or a symptom; it does not name the part that failed.
Note every code that is set, not just this one.
Codes that appear together usually narrow the cause faster than any one of them read alone.
Read the freeze frame — the conditions the fault was recorded under.
Cold or warm, idle or load, road speed and engine speed. A fault that only appears cold is a different fault from one that only appears under load, even with the same code on the scanner.
Confirm the fault is current rather than history.
Clear the code and see whether it returns under those same conditions. A code that does not come back may have been logged during a repair, a flat battery, or a bad connection that has since been disturbed.
Then follow the diagnostic notes further down this page, in the order they are written.
They are written in the order a shop works this code, cheapest checks first. Where they name a component, inspect its wiring and connector before replacing it.
If the code comes back after a repair, the underlying fault is still there. That is the point to bring in a scanner with live data and freeze-frame, or a shop that has one.
Common symptoms
- Check engine light
Read the full diagnostic procedureP0447 means the ECM commanded the EVAP vent valve (also called canister vent solenoid or CVS) to close for a leak test but detected an open electrica…
P0447 means the ECM commanded the EVAP vent valve (also called canister vent solenoid or CVS) to close for a leak test but detected an open electrical circuit on the control side - either the solenoid coil is open, the wiring to the solenoid is broken, or the PCM driver itself has failed. The vent valve sits at the charcoal canister and is normally open (allowing the canister to breathe atmosphere through a filter); the ECM commands it closed only when running an EVAP leak test.
Cheapest-first ladder
- locate the vent valve at the canister (usually under the vehicle near the rear axle on trucks/SUVs, or in the engine bay on some passenger cars) and unplug the connector.
- Measure the solenoid coil resistance across the two pins - a healthy EVAP vent solenoid reads 20 to 80 ohms (most domestic platforms cluster at 22 to 35 ohms; some imports run higher).
- Open circuit reading (OL on the meter) means the solenoid coil is burned open - replace the valve.
- If the solenoid resistance is in spec, key-on backprobe the connector for 12V on the power side and verify the ECM ground-side driver pulls the second pin to ground when commanded via scan tool bidirectional control.
- The expensive misdiagnosis is replacing the entire charcoal canister assembly when only the $30 to $80 vent solenoid has failed - on platforms with separately-serviceable vent valves, the solenoid is a standalone part that bolts to the canister, so verify before quoting the whole assembly.
Vehicle-specific patterns2007-2014 GM full-size trucks/SUVs (Silverado, Sierra, Suburban, Tahoe, Yukon 1500-3500) are the canonical P0447 platform - the vent valve mounts on…
- 2007-2014GM full-size trucks/SUVs (Silverado, Sierra, Suburban, Tahoe, Yukon 1500-3500) are the canonical P0447 platform - the vent valve mounts on top of the charcoal canister above the rear axle and the connector pigtail is a known rodent target because of the soybean-insulated GM wiring; mice nest in the canister and chew the vent solenoid wires open.
- 2009-2014Ford F-150 sees identical rodent-damage pattern on the frame-rail-mounted EVAP harness ahead of the canister.
- 2007-2014Toyota Tundra/Sequoia 5.7L throws P0447 from the vent valve coil failing internally open after road-salt corrosion penetrates the connector seal.
- 2009-2018RAM 1500 has the vent valve mounted at the rear of the fuel tank where road debris chips the connector housing and lets moisture into the solenoid, opening the coil. Subaru EJ-series sees vent valve coil failure from heat aging when the solenoid is mounted close to the exhaust.
Estimated repair$50 to $250.
Look up another code
More free tools