B1602 – OBD-II DTC

OBD-II DTC B1602 – PATS Received Invalid Format Of Key-Code From Ignition Key Transponder

DTC B1602 meaning

DTC B1602 refers to a diagnostic trouble code indicating that the Powertrain Control Module (PCM) has received an invalid format of the key-code from the ignition key transponder. This code is part of the Passive Anti-Theft System (PATS) and suggests that there is an issue with the communication between the key and the vehicle’s security system.

DTC B1602 symptoms

Common symptoms associated with DTC B1602 may include:

• The vehicle may not start.
• The security light on the dashboard may be illuminated.
• Intermittent starting issues.
• Loss of communication with the key transponder.

DTC B1602 causes

Several factors can lead to the occurrence of DTC B1602, including:

• Faulty ignition key transponder.
• Damaged or corroded wiring in the PATS system.
• Issues with the PCM or its programming.
• Weak or dead key fob battery.
• Incorrectly programmed or cloned key.

DTC B1602 seriousness

DTC B1602 is considered a serious issue as it can prevent the vehicle from starting, leaving the driver stranded. It indicates a potential security risk, as the vehicle’s anti-theft system is not functioning correctly. Addressing this code promptly is essential to ensure the vehicle’s reliability and security.

How to diagnose DTC B1602

To diagnose DTC B1602, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1602 code.
2. Inspect the ignition key for any visible damage or wear.
3. Check the key fob battery and replace it if necessary.
4. Examine the wiring and connectors related to the PATS system for any signs of damage or corrosion.
5. Test the key transponder using a specialized tool to ensure it is functioning correctly.
6. Check the PCM for any software updates or reprogramming needs.

How to fix DTC B1602 step-by-step instructions

To fix DTC B1602, follow these steps:

1. Replace the ignition key transponder if it is found to be faulty.
2. Repair or replace any damaged wiring or connectors in the PATS system.
3. Reprogram the key if it is incorrectly programmed or cloned.
4. Ensure the PCM is updated with the latest software version.
5. Clear the DTC using an OBD-II scanner and test the vehicle to ensure the issue is resolved.

How to erase DTC B1602

To erase DTC B1602, 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 start the vehicle to check if the code reappears.

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