Cylinder 5 Deactivation/Intake Valve Control Circuit Low
The P3435 code indicates that the powertrain control module (PCM) has detected a low voltage condition in the intake valve control circuit for cylinder 5's deactivation system. This system is used in some engines to disable cylinders under light load to improve fuel economy. The low voltage suggests a short to ground, open circuit, or faulty component in the circuit, which can prevent proper valve operation and cause drivability issues.
1. Most Common Causes
- Faulty cylinder 5 intake valve control solenoid or low internal resistance
- Short to ground in the solenoid control circuit wiring
- Damaged or corroded connector or pin in the solenoid harness
- Excessive resistance in circuit connections
- Internal failure of the engine control module (ECM/PCM) solenoid driver
- Mechanical issue in the valve deactivation mechanism (lifter, rocker arm, or locking pin)
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine misfire or rough idle
- Reduced fuel economy
- Possible hesitation or loss of power
3. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm P3435 and check for other codes.
Step 2: Visually inspect wiring and connectors for damage, corrosion, or loose connections.
Step 3: Test the cylinder 5 deactivation solenoid resistance and compare to specifications.
Step 4: Check for voltage and ground at the solenoid connector with the engine running.
Step 5: If wiring and solenoid 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 it can cause engine misfire, reduced performance, and potential catalytic converter damage. Have it diagnosed 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 including labor.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.