U1596 – Module Communication Failure

The ODBII code U1596 indicates a communication failure between modules in the vehicle’s network, suggesting that one or more electronic control units (ECUs) are not able to communicate properly with each other.

The severity of ODBII code U1596: Module Communication Failure is generally considered moderate to severe.

Common Causes For: 1. U1588: Module Communication Failure

• Faulty wiring or connectors
• Malfunctioning control module
• Corrupted software or firmware in the module
• Poor ground connections
• Interference from aftermarket devices
• Low battery voltage or power supply issues
• Communication network issues (e.g., CAN bus problems)
• Damaged or corroded pins in connectors

Common misdiagnosis for 1. U1596: Module Communication Failure

• Faulty wiring or connectors
• Defective control module
• Software issues or updates needed
• Battery or power supply problems
• Grounding issues
• Intermittent communication issues
• Other module failures (e.g., ABS, BCM)
• Corrupted data or configuration errors

Common Troubleshooting Steps

When dealing with OBD-II code U1596, which indicates a “Module Communication Failure,” it’s important to follow a systematic approach to troubleshoot the issue. Here are common troubleshooting steps:

• Check for Other Codes: Use an OBD-II scanner to check for any additional trouble codes. Sometimes, multiple codes can provide more context about the issue.
• Inspect Wiring and Connectors:
• Visually inspect the wiring and connectors associated with the affected module. Look for signs of damage, corrosion, or loose connections.
• Pay special attention to the ground connections, as poor grounding can lead to communication issues.
• Verify Power Supply:
• Ensure that the module in question is receiving the proper voltage and ground. Use a multimeter to check the power supply to the module.
• Check the vehicle’s fuses related to the module for any blown fuses.
• Check for Module Functionality:
• If possible, test the module itself to ensure it is functioning correctly. This may involve using specialized diagnostic tools or swapping the module with a known good one.
• Inspect the CAN Bus:
• U1596 often relates to issues with the Controller Area Network (CAN) bus. Check for any faults in the CAN bus wiring, such as shorts or opens.
• Use a CAN bus scanner to monitor the communication on the bus and identify any anomalies.
• Look for Interference:
• Check for any aftermarket devices or modifications that may interfere with the vehicle’s communication network. This includes alarm systems, stereo systems, or other electronic devices.
• Perform a Module Reset:
• Sometimes, simply resetting the module can resolve communication issues. This can be done by disconnecting the battery for a few minutes or using a scan tool to clear the codes.
• Update Software/Firmware:
• Check if there are any software or firmware updates available for the vehicle’s modules. Sometimes, manufacturers release updates to fix communication issues.
• Consult Technical Service Bulletins (TSBs):
• Look for any TSBs related to the specific make and model of the vehicle. Manufacturers may have documented known issues and solutions for U1596.
• Professional Diagnosis:
• If the issue persists after performing the above steps, consider seeking help from a professional mechanic or dealership. They may have access to advanced diagnostic tools and resources. By following these steps, you can systematically identify and resolve the underlying cause of the U1596 code.