• Warning light on the dashboard
• Loss of communication with certain vehicle functions
• Erratic vehicle behavior
• Faulty wiring or connections
• Defective control module
• Interference in the CAN bus network
CAN bus: A robust vehicle bus standard designed to allow microcontrollers and devices to communicate with each other.
Control Module: An electronic component that controls various functions in the vehicle.
• U0100
• U0121
This code means that the car's computer is having trouble talking to one of the parts that helps control the car. It's like when your phone can't connect to the internet.
This code indicates a communication problem between the vehicle's control modules.
U0679 is a diagnostic trouble code (DTC) that signifies a communication error between the vehicle's control modules over the Controller Area Network (CAN) bus. This error can occur if there is a failure in the data transmission or reception process.
• Check for other related codes
• Inspect wiring and connections for damage
• Test the CAN bus network for continuity
• Repair or replace damaged wiring
• Replace faulty control module
• Clear the code and test drive the vehicle
• OBD-II scanner
• Multimeter
• CAN bus diagnostic tool
$100 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect wiring for wear
• Keep electronic components dry
• Avoid aftermarket modifications that interfere with the CAN bus
Communication Issue
• Have a professional inspect the vehicle
• Avoid driving the vehicle until repaired if symptoms are severe
Check with your vehicle manufacturer to see if this issue is covered under warranty.
U0679 has been a common issue in vehicles with advanced electronic systems, particularly as vehicles have become more reliant on complex networks for communication.
Moderate – It is advisable to address this issue soon to prevent further complications.
Driving with a communication error may lead to unexpected vehicle behavior, which could be unsafe.
• Vehicle at operating temperature
• All electrical systems active
The control modules are typically located throughout the vehicle, often under the dashboard or in the engine bay.
Q: Can I drive with a U0679 code?
A: It's not recommended as it may cause erratic vehicle behavior.
Q: How do I clear a U0679 code?
A: After repairs, use an OBD-II scanner to clear the code.
