P1649 – Volkswagen DTC

Volkswagen DTC P1649 – Data Bus Powertrain Missing Message From Brake Controller

DTC P1649 meaning on Volkswagen

DTC P1649 on a Volkswagen indicates a communication error between the powertrain control module (PCM) and the brake controller. Specifically, it signifies that the PCM is not receiving a required message from the brake controller over the data bus.

Volkswagen DTC P1649 symptoms

Symptoms of DTC P1649 on a Volkswagen may include:

• Check Engine Light (MIL) illuminated
• Brake warning light may be on
• Issues with the transmission shifting smoothly
• Reduced engine performance

Volkswagen DTC P1649 causes

The common causes of DTC P1649 on a Volkswagen are:

• Faulty brake controller
• Wiring or connection issues between the PCM and brake controller
• Defective PCM
• Software issues

Volkswagen DTC P1649 seriousness

DTC P1649 should not be ignored as it can lead to potential safety hazards due to the communication breakdown between the PCM and the brake controller. It is recommended to address this issue promptly to ensure proper vehicle operation.

How to diagnose DTC P1649 on Volkswagen

To diagnose DTC P1649 on a Volkswagen, follow these steps:

1. Use a diagnostic scanner to retrieve the fault codes stored in the PCM.
2. Check the wiring and connections between the PCM and the brake controller for any damage or loose connections.
3. Inspect the brake controller for any signs of malfunction.
4. Perform a communication test between the PCM and the brake controller to identify any communication issues.

How to fix DTC P1649 on Volkswagen

To fix DTC P1649 on a Volkswagen, consider the following steps:

1. Repair or replace any damaged wiring or connections between the PCM and the brake controller.
2. If the brake controller is faulty, replace it with a new one.
3. Update the software in the PCM to the latest version.
4. Clear the fault codes using a diagnostic scanner after the repairs have been completed.

How to erase DTC P1649 on Volkswagen

To erase DTC P1649 on a Volkswagen, follow these steps:

1. Connect a diagnostic scanner to the vehicle’s OBD-II port.
2. Access the scanner’s menu to clear the fault codes stored in the PCM.
3. Follow the on-screen instructions to erase the DTC P1649 code.
4. Once the code has been cleared, perform a test drive to ensure the issue has been resolved.

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