Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the car's communication system, like when you can't talk to your friend because the phone line is down.
The C1105 code indicates an issue with the FlexRay communication system in the vehicle, which is responsible for high-speed data exchange between different vehicle components.
The FlexRay system is a high-speed communication network used in modern vehicles to connect various electronic control units (ECUs). The C1105 code suggests that there is an open circuit or a fault in the FlexRay High or Low lines, which can disrupt communication between these ECUs.
• Warning lights on the dashboard
• Loss of communication with certain vehicle systems
• Erratic vehicle behavior
• Damaged FlexRay wiring
• Faulty FlexRay module
• Poor electrical connections
FlexRay: A high-speed communication protocol used in automotive networks.
ECU: Electronic Control Unit, a computer that controls various functions in a vehicle.
• Inspect FlexRay wiring for damage or disconnections.
• Check electrical connections for corrosion or looseness.
• Test the FlexRay module for faults.
• Repair or replace damaged wiring.
• Clean and secure electrical connections.
• Replace the faulty FlexRay module.
• Multimeter
• OBD-II scanner
• Wire repair kit
$200 - $600
Moderate
• BMW 3 Series
• Mercedes-Benz C-Class
• Audi A4
• Regularly inspect wiring for damage.
• Ensure all electrical connections are secure.
• Avoid exposure of electronic components to moisture.
Communication Network Issue
• Do not ignore warning lights on the dashboard.
• Get the vehicle checked by a professional if you notice any unusual behavior.
Check with the vehicle manufacturer for warranty coverage on electronic components.
The C1105 code has become more common with the increasing use of advanced communication networks like FlexRay in modern vehicles.
Moderate – While the vehicle may still be drivable, the communication issue could lead to more serious problems if not addressed.
Ignoring communication issues can lead to safety risks due to potential loss of control over certain vehicle systems.
• Vehicle must be in a safe, controlled environment.
• All electronic systems should be powered on.
The FlexRay module is typically located near the vehicle's main electronic control unit, often under the dashboard or in the engine compartment.
Q: Can I drive with a C1105 code?
A: It's possible, but not recommended as it may lead to further issues.
Q: What is FlexRay?
A: FlexRay is a high-speed communication network used in vehicles to connect different electronic systems.
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