Evaporative Emission Control System Purge Control Valve Circuit Open
The purge control valve that lets fuel vapors from the charcoal canister into the engine isn't opening properly—like a stuck door preventing air flow. The ECU detects an electrical circuit problem with this valve and can't activate it to control emissions.
The ECU sends a control signal to the purge valve solenoid and monitors the circuit for proper voltage and resistance response. When the valve fails to respond or the circuit is open, the ECU detects the absence of expected feedback current or continuity.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Purge Valve Control Circuit Voltage | 12V when activated, 0V when de-energized | No voltage change or open circuit detected (>10 kΩ resistance) |
| Solenoid Coil Resistance | 10-30 ohms | Infinite resistance or >100 ohms (open circuit) |
Code P0445 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.
Once the fault is repaired, P0445 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.