Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car is having trouble talking to a part that helps control how the engine breathes. Imagine if your friend stopped responding during a game of telephone. The car's computer isn't getting a message it needs from one of the engine parts.
The P1040 code indicates a communication issue between the Variable Valve Lift (VVL) system and the engine control module (ECM) for Bank 2. The ECM is not receiving the expected message from the VVL system over the Controller Area Network (CAN).
The P1040 code is triggered when the ECM fails to receive the VVL message for Bank 2 within a specified timeframe. This message is crucial for adjusting the valve timing to optimize engine performance and efficiency. The CAN bus is the communication network that connects various control modules in the vehicle, and a timeout suggests a disruption or failure in this communication.
• Check Engine Light illuminated
• Reduced engine performance
• Poor fuel economy
• Faulty VVL actuator or solenoid
• Damaged or corroded wiring/connectors in the CAN bus
• Faulty ECM or software glitch
VVL: Variable Valve Lift
CAN: Controller Area Network
ECM: Engine Control Module
• Use an OBD-II scanner to confirm the P1040 code.
• Inspect the wiring and connectors for the VVL system and CAN bus.
• Test the VVL actuator and solenoid for proper operation.
• Repair or replace damaged wiring/connectors.
• Replace faulty VVL actuator or solenoid.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wiring repair tools
$150 - $600
Moderate
• Nissan Altima
• Infiniti G35
• Nissan Maxima
• Regular maintenance and inspection of electrical connections.
• Ensure software updates are applied to the ECM.
• Avoid exposure of electronics to moisture.
Communication Issue
• Have the vehicle inspected by a professional mechanic.
• Avoid driving long distances until the issue is resolved.
Check with your vehicle manufacturer; some powertrain warranties may cover ECM or VVL-related repairs.
This code has been associated with communication issues in vehicles with advanced valve timing systems, particularly in models with high mileage.
Moderate – While the vehicle may still be drivable, it can lead to reduced performance and efficiency.
Driving with a malfunctioning VVL system can lead to increased emissions and may not comply with local environmental regulations.
• Engine at operating temperature
• Vehicle idling or driving under normal conditions
The VVL actuator is typically located on the cylinder head of the engine, near the intake or exhaust valves.
Q: Can I drive with a P1040 code?
A: It's possible to drive with this code, but it's not recommended due to potential reduced engine performance and efficiency.
Q: Will a P1040 code affect my car's emissions?
A: Yes, it can lead to increased emissions due to improper valve timing.
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