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 a special communication line in your car. It's like when your phone can't send messages because the signal is too strong.
The FlexRay communication system is experiencing a high voltage condition on the low circuit line.
The C1103 code indicates that the FlexRay communication network, which is used in some vehicles for high-speed data transmission between different control units, has detected an unusually high voltage on the low circuit line. This could be due to a short circuit, a faulty module, or wiring issues.
• Warning lights on the dashboard
• Loss of communication between control modules
• Vehicle may enter a limp mode
• Short circuit in the FlexRay wiring
• Faulty FlexRay module
• Corroded or damaged connectors
FlexRay: A high-speed communication network used in vehicles.
OBD-II: On-Board Diagnostics, a system for vehicle self-diagnosis and reporting.
• Check for any other diagnostic trouble codes.
• Inspect the FlexRay wiring and connectors for damage.
• Test the FlexRay module for proper operation.
• Repair or replace damaged wiring.
• Clean or replace corroded connectors.
• Replace the faulty FlexRay module.
• OBD-II scanner
• Multimeter
• Wire repair kit
$200 - $600
Moderate
• BMW 5 Series
• Mercedes-Benz C-Class
• Audi A6
• Regularly inspect wiring and connectors.
• Avoid moisture exposure to electronic components.
• Ensure proper installation of aftermarket electronics.
Communication Network Issue
• Have the vehicle inspected by a professional.
• Avoid driving in harsh conditions until repaired.
Check with the vehicle manufacturer for warranty coverage related to electronic components.
The C1103 code has been associated with issues in vehicles that use FlexRay networks, particularly in European models.
Moderate – It should be addressed soon to avoid further communication issues.
Driving with unresolved communication issues can lead to safety risks and may affect vehicle performance.
• Vehicle parked and engine off.
• Access to the vehicle's diagnostic port.
The FlexRay module is typically located near the vehicle's main control units, often under the dashboard or in the engine bay.
Q: Can I drive with a C1103 code?
A: It's not recommended, as it may lead to further issues or unsafe driving conditions.
Q: How do I reset the C1103 code?
A: After repairs, use an OBD-II scanner to clear the code, but ensure the issue is resolved first.
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