Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer has a problem reading a specific memory chip that controls part of the engine.
The code indicates an error in the read-only memory (ROM) of the Variable Valve Lift (VVL) control module for the second bank of the engine.
The P1046 code is triggered when the engine control module (ECM) detects a malfunction in the ROM of the VVL control module on bank 2. The ROM is a critical component that stores essential data for the operation of the VVL system, which adjusts the valve lift for optimal engine performance.
• Check Engine Light on
• Reduced engine performance
• Poor fuel economy
• Faulty VVL control module
• Corrupted ROM data
• Wiring issues or poor connections
VVL: Variable Valve Lift
ROM: Read Only Memory
ECM: Engine Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the VVL control module.
• Test the VVL control module for faults.
• Replace the faulty VVL control module.
• Repair or replace damaged wiring or connectors.
• Reprogram or update the ECM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$300 - $800
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regular maintenance and inspections
• Ensure proper software updates
• Check for recalls related to the VVL system
Engine Performance
• Avoid hard driving until repaired.
• Have the vehicle inspected by a professional.
• Do not ignore the Check Engine Light.
Check if the vehicle's powertrain warranty covers the VVL system.
This code is relatively uncommon but can occur in vehicles with advanced VVL systems.
Moderate – Address the issue soon to prevent further engine performance problems.
Driving with this issue may lead to increased emissions and reduced fuel efficiency.
• Engine at operating temperature
• Vehicle in a safe, stationary position
The VVL control module is typically located near the engine, on the side corresponding to bank 2.
Q: What happens if I ignore the P1046 code?
A: Ignoring the code can lead to reduced engine performance and increased fuel consumption.
Q: Can I drive my car with a P1046 code?
A: It's possible to drive, but it's not recommended as it may cause further damage.
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