Cylinder 12 Exhaust Valve Control Circuit High
Code P3496 indicates that the powertrain control module (PCM) has detected a high voltage condition in the exhaust valve control circuit for cylinder 12. This circuit is part of a variable valve timing or cylinder deactivation system, commonly found in modern V8 or V12 engines. A high voltage reading suggests a short to power, open circuit, or faulty component in the solenoid or wiring.
01. Most Common Causes
- Faulty exhaust valve control solenoid on cylinder 12
- Short to battery voltage in the control circuit wiring
- Open or high resistance in the circuit
- Corroded or damaged connector at the solenoid
- Failed PCM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine misfire or rough idle
- Reduced engine power or performance
- Poor fuel economy
- Possible engine knocking or hesitation
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to verify the code and check for related codes (e.g., P3495, P3497).
Step 2: Visually inspect the wiring and connector for cylinder 12 exhaust valve solenoid for damage, corrosion, or loose pins.
Step 3: Measure voltage at the solenoid connector with the ignition on; should be battery voltage (12V) on one pin and ground on the other. If voltage is high (e.g., >12V), suspect a short to power.
Step 4: Test the solenoid resistance with a multimeter; compare to manufacturer specs (typically 10-30 ohms). Replace if out of range.
Step 5: If wiring and solenoid are okay, perform a circuit continuity test from PCM to solenoid. Repair open or short as needed.
Step 6: If all else fails, replace the PCM and reprogram.
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 engine may misfire, causing catalytic converter damage or reduced performance. Have it diagnosed promptly.
How much does it cost to fix?▼
Typical repair costs range from $50 to $150 for a solenoid replacement, plus diagnostic fees. Wiring repairs may add $100-$200.