U1190 – SCP (J1850) Invalid or Missing Data for Primary Id

The ODBII code U1190 SCP (J1850) Invalid or Missing Data for Primary Id indicates that the vehicle’s communication network is not receiving valid or expected data from a primary module, which may affect the operation of various systems.

The severity of ODBII code U1190 SCP (J1850) Invalid or Missing Data for Primary Id is moderate.

Common Causes For: U1189 SCP (J1850) Invalid or Missing Data for Primary Id

• Faulty or damaged wiring/connectors
• Malfunctioning or disconnected modules
• Communication network issues
• Low battery voltage
• Corrupted software or firmware in modules
• Interference from aftermarket devices
• Poor ground connections

Common misdiagnosis for U1190 SCP (J1850) Invalid or Missing Data for Primary Id

• Faulty O2 sensors
• Bad fuel injectors
• Malfunctioning mass air flow (MAF) sensor
• Defective engine control module (ECM)
• Wiring issues or shorts in the data bus
• Faulty battery or poor ground connections
• Issues with the vehicle’s ignition system
• Problems with the transmission control module (TCM)

Common Troubleshooting Steps

The OBD-II code U1190 indicates an issue with the SCP (Serial Communication Protocol) on the J1850 bus, specifically that there is invalid or missing data for the primary ID. This can be related to communication problems between modules in the vehicle. 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. This can provide additional context for the issue.
• Inspect Wiring and Connectors: Visually inspect the wiring and connectors associated with the J1850 bus. Look for signs of damage, corrosion, or loose connections.
• Pay special attention to the connectors on the modules that communicate over the J1850 bus.
• Check Battery Voltage: Ensure that the vehicle’s battery is fully charged and that the voltage is within the normal range (typically 12.4 to 12.6 volts when the engine is off).
• Check for any voltage drops or poor ground connections that could affect communication.
• Test the Communication Bus: Use a multimeter or an oscilloscope to check the voltage levels on the J1850 bus. You should see a specific voltage pattern when the vehicle is running.
• If you have access to a scan tool that can monitor live data, check the communication between modules to see if any are not responding.
• Inspect Modules: Identify the modules that communicate over the J1850 bus (e.g., PCM, BCM, ABS, etc.) and check for any signs of failure.
• If a specific module is suspected to be the issue, consider testing or replacing it.
• Check for Software Updates: Check if there are any software updates available for the vehicle’s modules. Sometimes, manufacturers release updates to fix communication issues.
• Clear Codes and Test Drive: After performing any repairs or inspections, clear the trouble codes and take the vehicle for a test drive to see if the code returns.
• Consult Technical Service Bulletins (TSBs): Look for any TSBs related to the U1190 code for your specific vehicle make and model. Manufacturers may have specific recommendations or known issues.
• Professional Diagnosis: If the issue persists after performing the above steps, consider seeking help from a professional mechanic or dealership. They may have specialized tools and knowledge to diagnose complex communication issues.Conclusion Troubleshooting OBD-II code U1190 involves a systematic approach to check for communication issues between modules. By following these steps, you can identify and resolve the underlying problem effectively.