B1601 – OBD-II DTC

OBD-II DTC B1601 – PATS Received Incorrect Key-Code From Ignition Key Transponder

DTC B1601 meaning

DTC B1601 refers to a diagnostic trouble code indicating that the Passive Anti-Theft System (PATS) has received an incorrect key code from the ignition key transponder. This code is triggered when the vehicle’s security system detects a mismatch between the key being used and the key codes stored in the vehicle’s computer system.

DTC B1601 symptoms

Common symptoms associated with DTC B1601 may include:

• The vehicle may not start.
• The security light on the dashboard may be illuminated.
• Intermittent starting issues may occur.
• Key recognition problems when using the ignition key.

DTC B1601 causes

Several factors can lead to the triggering of DTC B1601, including:

• A faulty ignition key or transponder.
• Issues with the PATS module or wiring.
• Corrosion or damage to the ignition switch.
• Incorrectly programmed or cloned keys.
• Faulty vehicle computer or software issues.

DTC B1601 seriousness

DTC B1601 is considered a serious issue as it directly affects the vehicle’s ability to start. If the vehicle cannot recognize the key, it may leave the driver stranded. Additionally, unresolved issues with the PATS can lead to further complications with the vehicle’s security system.

How to diagnose DTC B1601

To diagnose DTC B1601, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1601 code.
2. Inspect the ignition key for any visible damage or wear.
3. Check the PATS module and wiring for any signs of damage or corrosion.
4. Test the transponder in the key to ensure it is functioning correctly.
5. Verify that the key is correctly programmed to the vehicle.

How to fix DTC B1601 step-by-step instructions

To fix DTC B1601, follow these steps:

1. Replace the ignition key if it is damaged or worn.
2. Reprogram the key using the vehicle’s programming procedure.
3. Inspect and repair any damaged wiring or connectors related to the PATS.
4. Replace the PATS module if it is found to be faulty.
5. Clear the DTC using an OBD-II scanner and test the vehicle to ensure the issue is resolved.

How to erase DTC B1601

To erase DTC B1601, 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 trouble codes.
4. Confirm the action and wait for the scanner to complete the process.
5. Disconnect the scanner and start the vehicle to check if the code reappears.

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