U1797 – OBD-II DTC

OBD-II DTC U1797 – SCP (J1850) Lack of Acknowledgment for Door Locks

DTC U1797 meaning

DTC U1797 refers to a communication issue within the vehicle’s network, specifically related to the door lock system. The code indicates a “Lack of Acknowledgment” for the door locks when using the SCP (Single Wire Communication Protocol) over the J1850 communication bus. This means that the control module responsible for the door locks is not receiving a response from another module, which can lead to malfunctioning door locks.

DTC U1797 symptoms

Common symptoms associated with DTC U1797 may include:

• Inoperable door locks (either manual or automatic)
• Door lock switches not functioning
• Inconsistent door lock operation
• Other related features, such as remote keyless entry, may also be affected

DTC U1797 causes

Several factors can lead to the occurrence of DTC U1797, including:

• Faulty door lock actuator
• Wiring issues, such as damaged or corroded connectors
• Malfunctioning control module for the door locks
• Communication issues within the vehicle’s network
• Software glitches in the control modules

DTC U1797 seriousness

The seriousness of DTC U1797 can vary. While it may not pose an immediate safety risk, it can lead to inconvenience due to non-functioning door locks. If left unaddressed, it may indicate underlying issues with the vehicle’s electrical system that could affect other components.

How to diagnose DTC U1797

To diagnose DTC U1797, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the U1797 code.
2. Check for any additional DTCs that may provide more context.
3. Inspect the wiring and connectors related to the door lock system for damage or corrosion.
4. Test the door lock actuator for proper operation.
5. Verify communication between the control modules using a scan tool.
6. Check for software updates or reprogramming needs for the control modules.

How to fix DTC U1797 step-by-step instructions

To fix DTC U1797, follow these steps:

1. Inspect and repair any damaged wiring or connectors related to the door lock system.
2. Replace the door lock actuator if it is found to be faulty.
3. Reprogram or update the control module software if necessary.
4. Clear the DTC using an OBD-II scanner.
5. Test the door locks to ensure they are functioning properly.

How to erase DTC U1797

To erase DTC U1797, perform the following steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Access the diagnostic menu and select the option to clear or erase DTCs.
3. Confirm the action to erase the codes.
4. Disconnect the scanner and start the vehicle to check if the code reappears.

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