U1862 – Network Communication Line Fault

The ODBII code U1862 indicates a fault in the network communication line, suggesting a problem with the data transmission between modules in the vehicle’s communication network.

The severity of ODBII code U1862 is moderate.

Common Causes For: U1861 U1861: “Module Communication Line Fault”

• Damaged wiring or connectors
• Faulty control modules
• Poor ground connections
• Short circuits in the communication line
• Intermittent connections
• Corroded terminals
• Faulty or incompatible aftermarket accessories
• Software issues or bugs in the control modules

Common misdiagnosis for U1862 U1862: “Network Communication Line Fault”

• Faulty wiring or connectors
• Defective control modules
• Poor ground connections
• Intermittent communication issues
• Incorrectly configured or programmed modules
• Faulty sensors
• Battery or power supply issues
• Software glitches or updates needed

Common Troubleshooting Steps

The OBD-II code U1862 indicates a “Network Communication Line Fault.” This code typically points to issues with the communication between various modules in the vehicle’s network, such as the Controller Area Network (CAN) bus. Here are some common troubleshooting steps to diagnose and resolve the issue:

• Check for Additional Codes: Use an OBD-II scanner to check for any other trouble codes that may be present. Sometimes, multiple codes can provide more context for the issue.
• Inspect Wiring and Connectors: Visually inspect the wiring and connectors associated with the CAN bus. Look for signs of damage, corrosion, or loose connections.
• Pay special attention to the connectors at the modules involved in the communication.
• Test the CAN Bus: Use a multimeter or an oscilloscope to check the voltage levels on the CAN bus wires. The typical voltage levels should be around 2.5V to 2.8V when the bus is idle.
• Check for short circuits or open circuits in the CAN bus wiring.
• Check for Ground Issues: Ensure that all ground connections related to the modules are secure and free of corrosion. Poor grounding can lead to communication issues.
• Inspect Modules: Identify the modules that are part of the communication network. Check for any signs of failure or damage.
• If possible, test the modules individually to ensure they are functioning correctly.
• Look for Interference: Check for any aftermarket devices or modifications that may interfere with the vehicle’s communication network. This includes alarms, stereo systems, or other electronic devices.
• Perform a Network Test: Some advanced scan tools can perform a network test to check the integrity of the communication lines. Use this feature if available.
• Reset the Codes: After performing inspections and repairs, clear the codes using the OBD-II scanner and take the vehicle for a test drive to see if the code returns.
• Consult Technical Service Bulletins (TSBs): Check for any TSBs related to the specific make and model of the vehicle. Manufacturers may have issued guidance on common issues related to the U1862 code.
• Seek Professional Help: If the issue persists after performing the above steps, it may be necessary to consult a professional mechanic or technician who has experience with automotive electrical systems and can perform more in-depth diagnostics. By following these steps, you should be able to identify and resolve the underlying issue causing the U1862 code.