U1519 – Transmission Control Module Communication Error

The ODBII code U1519 indicates a communication error between the Transmission Control Module (TCM) and other control modules in the vehicle, suggesting a possible issue with wiring, connectors, or the TCM itself.

The severity of ODBII code U1519 is generally considered moderate to severe.

Common Causes For: U1518 U1518: TCM Communication Failure

• Faulty Transmission Control Module (TCM)
• Damaged wiring or connectors
• Poor electrical connections
• Failed or malfunctioning Engine Control Module (ECM)
• Software issues or programming errors
• Low battery voltage or electrical system problems
• Corroded terminals or connectors
• Faulty CAN bus communication
• Grounding issues in the vehicle’s electrical system

Common misdiagnosis for U1519 U1519: Transmission Control Module Communication Error

• Faulty Transmission Control Module (TCM)
• Wiring issues or damaged connectors
• Faulty Engine Control Module (ECM)
• Low transmission fluid levels
• Transmission solenoid problems
• Faulty sensors (e.g., speed sensors)
• Software issues or outdated firmware
• Electrical system problems (e.g., battery or alternator issues)

Common Troubleshooting Steps

The OBD-II code U1519 indicates a communication error between the Transmission Control Module (TCM) and other control modules in the vehicle. Here are some common troubleshooting steps to diagnose and resolve this issue:

• Check for Other Codes: Use an OBD-II scanner to check for any additional trouble codes. Sometimes, related codes can provide more context for the issue.
• Inspect Wiring and Connectors:
• Visually inspect the wiring harness and connectors related to the TCM. Look for signs of damage, corrosion, or loose connections.
• Ensure that all connectors are securely plugged in and that there are no bent pins.
• Check for Ground Issues:
• Verify that the TCM has a good ground connection. A poor ground can lead to communication errors.
• Use a multimeter to check for continuity between the TCM ground and the vehicle chassis.
• Test the TCM:
• If possible, test the TCM for proper operation. This may involve using specialized diagnostic equipment or swapping in a known good module.
• Check for any signs of physical damage to the TCM.
• Inspect the CAN Bus:
• The TCM communicates with other modules via the Controller Area Network (CAN) bus. Inspect the CAN bus wiring for damage or shorts.
• Use a scan tool to monitor the CAN bus for any irregularities in communication.
• Check Power Supply:
• Ensure that the TCM is receiving the correct voltage and that the power supply circuit is functioning properly.
• Check fuses related to the TCM and transmission system.
• Clear Codes and Test Drive:
• After performing the above checks and repairs, clear the trouble codes using the OBD-II scanner.
• Take the vehicle for a test drive to see if the code reappears.
• Software Updates:
• Check if there are any software updates available for the TCM or other related modules. Sometimes, manufacturers release updates to fix communication issues.
• Consult Technical Service Bulletins (TSBs):
• Look for any TSBs related to the U1519 code for your specific vehicle make and model. Manufacturers may have specific recommendations for addressing this issue.
• Professional Diagnosis:
• If the problem persists after performing these 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 diagnose and potentially resolve the U1519 code.