How severe is this DTC?
The severity of this code can vary significantly from moderate to severe depending on the specific symptoms of the malfunction. A misfire requires immediate attention as it can cause permanent damage to internal engine components.
What are some symptoms of the code?
Symptoms of a P3403 trouble code may include:
- Engine may misfire
- Increased fuel consumption
- Poor engine performance
- Service engine soon light illuminated
- Check engine light on
What are some common causes of the code?
Causes
of this P3403 code may include:
- Faulty cylinder deactivation solenoid
- Low engine oil level or pressure
- Restricted oil passage
- Faulty or damaged wiring
- Corroded, damaged, or loose connector
- Faulty ECM
What are the troubleshooting steps for P3403?
The first step in the troubleshooting process for any malfunction is to search for Technical Service Bulletins (TSBs) for the specific vehicle by year, model, and engine. In some circumstances, this can save you significant time in the long run by pointing you in the right direction.
The second step is to check the engine oil condition and confirm it is maintained at the appropriate level. Then locate all components associated with the cylinder 1 deactivation intake valve control circuit and look for obvious physical damage. Based on the specific vehicle, this circuit may incorporate multiple components, including the deactivation solenoid, switches, fault indicators, and the ECM. Perform a thorough visual inspection to verify that the associated wiring shows no obvious defects such as scraping, rubbing, bare wires, or burn marks. Next, check connectors and connections for security, corrosion, and damaged pins. This process should include all wiring connectors and connections to all components, including the ECM. Consult vehicle-specific technical data to verify the cylinder 1 deactivation/intake valve control circuit configuration and confirm each component incorporated in the circuit that may include a fuse or fusible link.
Advanced Steps
Advanced steps become very vehicle-specific and require appropriate advanced equipment to perform accurately. These procedures require a digital multimeter and vehicle-specific technical references.
Voltage Checks
Reference voltage and acceptable ranges may vary depending on the specific vehicle and circuit configuration. Specific technical data will include troubleshooting charts and the proper sequence to follow to help you establish an accurate diagnosis.
If this process identifies the absence of a power source or ground, continuity tests may be required to verify the integrity of wiring, connectors, and other components. Continuity tests should always be performed with power disconnected from the circuit, and normal readings for wiring and connections should be 0 ohms resistance. Resistance or lack of continuity is an indication of faulty wiring that is open, shorted, or corroded and should be repaired or replaced.
What are the common repairs for this code?
- Replacement of deactivation solenoid
- Cleaning corrosion from connectors
- Repairing or replacing faulty wiring
- Changing oil and filter
- Cleaning blocked oil passages
- ECM replacement
Common Mistake
Replacing the deactivation solenoid when insufficient oil pressure or faulty wiring causes the ECM to set this code.
I hope the information contained in this article has been helpful in pointing you in the right direction to correct the issue with the cylinder 1 deactivation/intake valve control circuit fault code. This article is strictly informational, and technical data and service bulletins specific to your vehicle should always take priority.