P1626 – OBD-II DTC

OBD-II DTC P1626 – Control Module Long Term Memory Performance/ Immobilizer Code Words Do Not Match

DTC P1626 meaning

DTC P1626 refers to a diagnostic trouble code indicating that the control module’s long-term memory performance is compromised, and the immobilizer code words do not match. This code is often related to issues with the vehicle’s security system, which may prevent the engine from starting. The control module is unable to verify the correct immobilizer code, leading to potential security concerns.

DTC P1626 symptoms

Common symptoms associated with DTC P1626 may include:

• Engine not starting
• Intermittent starting issues
• Dashboard warning lights illuminated, particularly the security or check engine light
• Loss of communication with the immobilizer system

DTC P1626 causes

Several factors can lead to the triggering of DTC P1626, including:

• Faulty or damaged control module
• Corrupted or missing immobilizer code
• Wiring issues, such as shorts or open circuits in the immobilizer system
• Defective key or key fob
• Software issues within the control module

DTC P1626 seriousness

DTC P1626 is considered a serious issue as it directly affects the vehicle’s ability to start. If the immobilizer system is not functioning correctly, it can lead to a no-start condition, leaving the driver stranded. Additionally, unresolved issues may lead to further complications within the vehicle’s electronic systems.

How to diagnose DTC P1626

To diagnose DTC P1626, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P1626 code.
2. Check for any additional trouble codes that may provide more context.
3. Inspect the vehicle’s wiring and connectors related to the control module and immobilizer system for damage or corrosion.
4. Test the key or key fob to ensure it is functioning correctly.
5. Verify that the control module is receiving proper power and ground signals.
6. Check for software updates or reprogramming needs for the control module.

How to fix DTC P1626 step-by-step instructions

To fix DTC P1626, follow these steps:

1. Repair or replace any damaged wiring or connectors found during diagnosis.
2. If the key or key fob is defective, replace it with a new one.
3. Reprogram the control module if necessary, following the manufacturer’s guidelines.
4. Clear any stored trouble codes using an OBD-II scanner.
5. Test the vehicle to ensure that the issue is resolved and the engine starts without problems.

How to erase DTC P1626

To erase DTC P1626, perform the following steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn the ignition key to the “On” position without starting the engine.
3. Access the trouble codes menu on the scanner.
4. Select the option to clear or erase trouble codes.
5. Confirm the action and wait for the scanner to complete the process.
6. Disconnect the scanner and start the vehicle to check if the code returns.

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