U1342 – Module Communication Failure

The ODBII code U1342 indicates a communication failure between modules in the vehicle’s network, suggesting that one or more control modules are not communicating properly with each other.

The severity of ODBII code U1342: Module Communication Failure is generally considered moderate to severe.

Common Causes For: 1. U1340: Control Module Communication Error

• Faulty wiring or connectors
• Failed control module
• Corrupted software or firmware
• Poor ground connections
• Interference from aftermarket devices
• Low battery voltage
• Communication network issues (e.g., CAN bus problems)

Common misdiagnosis for 1. U1342: 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

The OBD-II code U1342 indicates a “Module Communication Failure,” which typically means that there is a problem with communication between the vehicle’s control modules. Here are some common troubleshooting steps to diagnose and resolve this 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 affected module(s). Look for signs of damage, corrosion, or loose connections.
• Pay special attention to ground connections, as poor grounding can lead to communication issues.
• Check Power Supply:
• Ensure that the affected module is receiving the proper voltage. Use a multimeter to check the power supply to the module.
• Verify that the fuses related to the module are intact and functioning.
• Reset the Modules:
• Clear the trouble codes using an OBD-II scanner and see if the code returns after a short drive. Sometimes, a temporary glitch can cause communication issues.
• Inspect the CAN Bus:
• If your vehicle uses a Controller Area Network (CAN) bus for communication, check for any faults in the bus wiring. Look for shorts, opens, or damaged segments in the wiring harness.
• Use a CAN bus diagnostic tool if available to check for communication errors.
• Check for Software Updates:
• Some manufacturers release software updates for their modules. Check if there are any updates available for the affected module(s) and apply them if necessary.
• Test the Affected Module:
• If the above steps do not resolve the issue, the affected module may be faulty. Consider testing or replacing the module to see if that resolves the communication failure.
• Consult Technical Service Bulletins (TSBs):
• Look for any TSBs related to the specific make and model of your vehicle. Manufacturers may have documented common issues and solutions for specific models.
• Professional Diagnosis:
• If you are unable to resolve the issue, consider seeking help from a professional mechanic or dealership. They may have specialized diagnostic tools and experience with your vehicle’s specific systems. By following these steps, you should be able to identify and potentially resolve the communication failure indicated by the U1342 code.