U1171 – OBD-II DTC

OBD-II DTC U1171 – SCP (J1850) Invalid or Missing Data for Cellular Phone / Paging System

DTC U1171 meaning

DTC U1171 refers to a diagnostic trouble code indicating an issue with the Serial Communication Protocol (SCP) related to the cellular phone or paging system in a vehicle. This code signifies that the data being transmitted or received is either invalid or missing, which can affect the functionality of the communication systems within the vehicle.

DTC U1171 symptoms

Common symptoms associated with DTC U1171 may include:

• Inoperative cellular phone or paging system
• Communication errors with other modules
• Warning lights illuminated on the dashboard
• Intermittent connectivity issues

DTC U1171 causes

Several factors can lead to the triggering of DTC U1171, including:

• Faulty wiring or connectors in the SCP network
• Malfunctioning cellular phone or paging module
• Software issues within the vehicle’s control modules
• Corrosion or damage to the communication ports

DTC U1171 seriousness

The seriousness of DTC U1171 can vary. While it may not pose an immediate safety risk, it can lead to a loss of functionality in communication systems, which may affect driver convenience and vehicle diagnostics. It is advisable to address this code promptly to ensure all systems are operating correctly.

How to diagnose DTC U1171

To diagnose DTC U1171, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the U1171 code.
2. Inspect the wiring and connectors related to the SCP network for any visible damage or corrosion.
3. Check the functionality of the cellular phone or paging module.
4. Review any related codes that may provide additional context.
5. Perform a continuity test on the communication lines.

How to fix DTC U1171 step-by-step instructions

To fix DTC U1171, follow these steps:

1. Repair or replace any damaged wiring or connectors found during the inspection.
2. Replace the faulty cellular phone or paging module if necessary.
3. Update the software in the vehicle’s control modules if applicable.
4. Clear any corrosion from communication ports and ensure a secure connection.
5. Re-scan the vehicle to confirm that the DTC has been resolved.

How to erase DTC U1171

To erase DTC U1171, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Access the trouble codes menu on the scanner.
3. Select the option to clear or erase codes.
4. Confirm the action and wait for the scanner to complete the process.
5. Disconnect the scanner and take the vehicle for a test drive to ensure the code does not return.

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