p0446
Moderate
Cadillac · Sedans
Evaporative Emission Control System Vent Control Circuit
Quick Answer
Error code P0446 on your Cadillac Sedans means: Evaporative Emission Control System Vent Control Circuit. This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
How to Fix It
1
Check vent valve electrical connections
2
Test vent solenoid voltage with multimeter
3
Inspect vent line for blockages
4
Verify vacuum supply to vent system
5
Replace vent solenoid if faulty
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
Vent solenoid valve
Vacuum hose
Wiring harness
Multimeter
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