Cylinder 9 Exhaust Valve Control Circuit Low
The P3471 code indicates that the powertrain control module (PCM) has detected a low voltage condition in the exhaust valve control circuit for cylinder 9. This circuit is part of a variable valve timing or cylinder deactivation system, and a low voltage reading suggests a short to ground, open circuit, or faulty component. The issue can cause improper valve operation, leading to reduced engine performance, increased emissions, and potential engine damage if not addressed.
01. Most Common Causes
- Faulty exhaust valve control solenoid for cylinder 9
- Short to ground or open in the control circuit wiring
- Corroded or damaged connector at the solenoid or PCM
- Failed PCM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Rough idle or misfire on cylinder 9
- Reduced engine power and fuel economy
- Possible engine hesitation or stalling
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data. Clear codes and test drive to confirm code returns.
Step 2: Visually inspect the wiring and connector for cylinder 9 exhaust valve control circuit for damage, corrosion, or loose connections.
Step 3: Use a multimeter to check for continuity and shorts in the circuit between the solenoid and PCM. Compare resistance to specifications.
Step 4: Test the exhaust valve control solenoid by applying battery voltage and ground; listen for a click and measure resistance. Replace if out of spec.
Step 5: If circuit and solenoid are good, suspect a PCM fault; perform a PCM reflash or replacement as a last resort.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as the issue can cause engine misfire, reduced performance, and potential damage to the catalytic converter or engine. Have it diagnosed and repaired promptly.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and repair, depending on the cause. Replacing a solenoid may cost $100-$200, while wiring repairs are usually less.