U1169 – SCP (J1850) Invalid or Missing Data for Primary Id

The ODBII code U1169 SCP (J1850) indicates that there is invalid or missing data for the primary identifier in the vehicle’s communication network, specifically related to the SCP (Serial Communication Protocol) using the J1850 standard.

The severity of ODBII code U1169 is typically considered moderate.

Common Causes For: U1168 SCP (J1850) Invalid or Missing Data for Primary Id

• Faulty or damaged wiring/connectors
• Malfunctioning or disconnected sensors
• Issues with the vehicle’s PCM (Powertrain Control Module)
• Communication problems between modules
• Corrupted or outdated software/firmware
• Low battery voltage or poor electrical connections
• Interference from aftermarket devices or modifications

Common misdiagnosis for U1169 SCP (J1850) Invalid or Missing Data for Primary Id

• Faulty PCM (Powertrain Control Module)
• Bad wiring or connectors
• Defective sensors
• Communication issues between modules
• Incorrectly programmed or updated software
• Battery or power supply issues
• Grounding problems

Common Troubleshooting Steps

The OBD-II code U1169 indicates an issue with the SCP (Serial Communication Protocol) related to the J1850 communication bus, specifically indicating that there is invalid or missing data for the primary ID. 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 the Wiring and Connectors: **Visual Inspection: Check the wiring and connectors associated with the J1850 communication bus for any signs of damage, corrosion, or loose connections.
• **Repair or Replace: Repair any damaged wires or connectors as necessary.
• Check the Battery and Ground Connections: Ensure that the vehicle’s battery is in good condition and that all ground connections are secure. Poor ground connections can lead to communication issues.
• Test the Communication Network: Use a multimeter or an oscilloscope to test the voltage levels on the J1850 bus. Ensure that the voltage levels are within the expected range.
• Check for short circuits or open circuits in the communication lines.
• Inspect Modules: Check the modules that communicate over the J1850 bus (e.g., PCM, BCM, ABS, etc.) for any signs of failure. A malfunctioning module can cause communication issues.
• If possible, perform a module reset or reprogramming if the manufacturer provides such procedures.
• Check for Interference: Look 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 Scan Tool Communication Test: Use a professional scan tool to perform a communication test with the various modules. This can help identify if a specific module is not responding.
• Update Software/Firmware: Check if there are any software or firmware updates available for the vehicle’s modules. Sometimes, manufacturers release updates to fix known communication issues.
• Clear Codes and Test Drive: After performing the above checks and repairs, 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 specific make and model of the vehicle. Manufacturers may have issued guidance on common issues related to the U1169 code.1
• Seek Professional Help: If the issue persists after performing the above steps, it may be necessary to consult a professional mechanic or technician who specializes in automotive electronics. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the U1169 code.