Fault code U1080 – a step-by-step guide to diagnosing and fixing it

Error code U1080 is displayed and the check engine light is on - what does this mean?

The DTC U1080 is a manufacturer-specific error code that is recognized by the OBD and EOBD systems and indicates a communication problem in the CAN bus network. This trouble code occurs when communication between different control units is interrupted or disrupted. This fault code can have slightly different meanings for different manufacturers, but basically refers to network communication errors.

What causes can this fault code have?

• Defective CAN bus cable or damaged wiring
• Corroded or loose plug connections in the network
• Failed or defective control unit (ECU)
• Short circuit or interruption in the CAN bus cable
• Defective terminating resistors in the CAN bus system
• Malfunctions due to electromagnetic interference
• Voltage problems in the vehicle battery
• Water damage to electronic components

Which symptoms occur in parallel with error code U1080?

• Communication faults: Various vehicle systems do not function properly or fail completely
• Warning lights: Multiple indicator lights illuminate simultaneously in the dashboard
• Functional failure: ABS, ESP, air conditioning or other electronic systems work unreliably
• Starting problems: The vehicle is difficult to start or does not start at all
• Instrument failure: speedometer, rev counter or other displays work intermittently

How to fix the problem of error code U1080?

• Repairing error code U1080 requires a systematic diagnosis of the CAN bus network.
• Checking and cleaning all CAN bus connectors, replacing corroded connectors and ensuring tight connections
• Measuring the CAN bus cables with a multimeter for continuity, short circuits and correct resistance values between the cables
• Replacing damaged CAN bus cables and repairing cable breaks or chafing points in the cabling
• Diagnosis and replacement of defective control units by isolating individual modules and checking their communication capability
• Checking and replacing the vehicle battery and charging system in the event of voltage problems below 12V
• Professional diagnostics with manufacturer-specific diagnostic devices to identify the exact communication error