Cylinder 10 Exhaust Valve Control Circuit Low
The P3479 code indicates that the powertrain control module (PCM) has detected a low voltage condition in the exhaust valve control circuit for cylinder 10. This circuit is responsible for controlling the variable valve timing or cylinder deactivation system. A low voltage reading suggests a short to ground, a faulty actuator, or a wiring issue, which can prevent the exhaust valve from operating correctly, leading to reduced engine performance and increased emissions.
1. Most Common Causes
- Faulty cylinder 10 exhaust valve actuator solenoid or altered internal resistance
- Short to ground in the control circuit wiring
- Corroded, loose, or damaged connector or terminal
- Excessive circuit resistance due to poor splices or deteriorated wiring
- Internal failure of the engine control module (ECM/PCM) circuit driver
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Rough idle or misfire on cylinder 10
- Reduced engine power and fuel economy
- Possible engine hesitation or stalling
3. Step-by-Step Diagnosis
Step 1: Use a scan tool to retrieve all codes and freeze frame data.
Step 2: Inspect wiring and connector at cylinder 10 for damage, corrosion, or shorts.
Step 3: Test the exhaust valve actuator resistance and compare to specifications.
Step 4: Check for power and ground at the actuator connector with a multimeter.
Step 5: If wiring and actuator are good, test the PCM output circuit.
4. 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.
How much does it cost to fix?▼
Repair costs typically range from $150 to $400, depending on whether the actuator or wiring needs replacement and labor rates.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.