P1684 – OBD-II DTC

OBD-II DTC P1684 – Electronic Feedback Signal Not Detected

DTC P1684 meaning

DTC P1684 refers to an issue where the Electronic Feedback Signal is not detected by the vehicle’s onboard diagnostic system. This code is typically associated with the vehicle’s ignition system and can indicate a problem with the communication between the engine control module (ECM) and the ignition switch. The absence of this signal can lead to various operational issues within the vehicle.

DTC P1684 symptoms

Common symptoms associated with DTC P1684 may include:

• Engine not starting or stalling
• Intermittent electrical issues
• Dashboard warning lights illuminated
• Loss of power or performance

DTC P1684 causes

Several factors can lead to the triggering of DTC P1684, including:

• Faulty ignition switch
• Wiring issues or damaged connectors
• Defective engine control module (ECM)
• Corrosion or poor connections in the electrical system

DTC P1684 seriousness

DTC P1684 can be considered a moderate to serious issue. If left unaddressed, it may lead to further electrical problems, potential engine failure, or safety concerns while driving. It is advisable to diagnose and resolve this code promptly to ensure the vehicle operates safely and efficiently.

How to diagnose DTC P1684

To diagnose DTC P1684, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P1684 code.
2. Inspect the ignition switch for proper operation.
3. Check wiring and connectors for damage or corrosion.
4. Test the engine control module (ECM) for faults.
5. Clear the code and perform a road test to see if the code reappears.

How to fix DTC P1684 step-by-step instructions

To fix DTC P1684, follow these steps:

1. Replace the faulty ignition switch if it is not functioning correctly.
2. Repair or replace any damaged wiring or connectors.
3. Clean any corrosion found in the electrical connections.
4. If necessary, replace the engine control module (ECM).
5. Recheck the system with an OBD-II scanner to ensure the code is cleared.

How to erase DTC P1684

To erase DTC P1684, you can follow these 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 codes.
3. Confirm the action and wait for the scanner to complete the process.
4. Disconnect the scanner and perform a test drive to ensure the code does not return.

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