U1166 – SCP (J1850) Invalid or Missing Data for Cassette Tape

The ODBII code U1166 SCP (J1850) Invalid or Missing Data for Cassette Tape indicates a communication issue within the vehicle’s network, specifically related to the cassette tape player, where the expected data is either invalid or not being received.

The severity of ODBII code U1166 SCP (J1850) Invalid or Missing Data for Cassette Tape is typically considered low.

Common Causes For: U1165 U1165: “Module Communication Failure”

• Faulty cassette tape player
• Poor electrical connections
• Damaged wiring or connectors
• Malfunctioning vehicle communication network
• Software or firmware issues
• Corrupted data signals
• Faulty or incompatible aftermarket audio equipment

Common misdiagnosis for U1166 SCP (J1850) Invalid or Missing Data for Cassette Tape

• Faulty audio system components
• Wiring issues or shorts in the audio system
• Malfunctioning vehicle communication network
• Incorrectly configured or incompatible aftermarket audio equipment
• Software glitches in the vehicle’s infotainment system
• Faulty or damaged connectors related to the audio system
• Issues with the vehicle’s battery or power supply affecting the audio system

Common Troubleshooting Steps

The OBD-II code U1166 indicates an issue with the SCP (Serial Communication Protocol) related to the J1850 communication bus, specifically pointing to invalid or missing data for the cassette tape system. Here are some common troubleshooting steps to address this code:

• 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: Examine the wiring and connectors related to the cassette tape system and the J1850 communication bus. Look for signs of damage, corrosion, or loose connections that could affect communication.
• Test the Cassette Tape Player: If the vehicle is equipped with a cassette tape player, ensure that it is functioning correctly. Try playing a cassette tape to see if the player operates as expected.
• Check the Vehicle’s Battery and Ground Connections: Ensure that the vehicle’s battery is in good condition and that all ground connections are secure. Poor power or ground can lead to communication issues.
• Inspect the Audio System: If the vehicle has an integrated audio system, check for any faults in the audio components that may be affecting communication. This includes checking the radio and any related modules.
• Scan for Communication Issues: Use a professional-grade scan tool to monitor the communication between modules. Look for any anomalies or failures in data transmission.
• Update Software/Firmware: If applicable, check if there are any software or firmware updates available for the vehicle’s modules. Sometimes, updates can resolve communication issues.
• Perform a Hard Reset: Disconnect the vehicle’s battery for a few minutes to reset the modules. Reconnect the battery and see if the code reappears.
• Check for Environmental Factors: Ensure that there are no external factors (like moisture or extreme temperatures) affecting the cassette tape system or the communication bus.
• 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 resolving similar issues. 1
• Seek Professional Help: If the issue persists after performing the above steps, consider consulting a professional mechanic or automotive technician who has experience with the specific vehicle and its systems. By following these troubleshooting steps, you can systematically identify and resolve the issue related to the U1166 code.