P0644 Fault Code

Driver Display Serial Communication Circuit

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0644 fault code indicates an issue with the Driver Display Serial Communication Circuit. This circuit is crucial for the communication between the vehicle's electronic control units (ECU) and the driver display, which provides the driver with important information about the vehicle's performance and status.

• This fault code can disrupt various functions related to the driver display, leading to less accurate readings and warnings.
• It is important to diagnose and address this code promptly to ensure the reliability of the vehicle's display systems.

What are the symptoms of the P0644 code?

Common symptoms associated with the P0644 fault code include:

• Malfunctioning or blank driver display.
• Incorrect readings on the dashboard (e.g., speed, fuel level).
• Warning lights illuminated on the dashboard.
• Flickering or inconsistent display functions.

What causes the P0644 code?

The P0644 code can be triggered by several factors, including:

• Damaged or corroded wiring in the serial communication circuit.
• Faulty connectors that may lead to intermittent connectivity.
• Defective driver display unit or ECU.
• Issues with related sensors or modules that communicate with the driver display.

How to fix P0644?

To resolve the P0644 fault code, the following steps should be taken:

• Perform a visual inspection of the wiring and connectors for any signs of damage or corrosion.
• Use a multimeter to check for continuity and proper voltage in the serial communication circuit.
• Replace or repair any faulty wires or connectors found during inspection.
• If the wiring and connectors are in good condition, consider testing the driver display unit and ECU for faults and replacing them if necessary.