• Warning lights on the dashboard
• Loss of certain safety features
• Erratic vehicle behavior
• Faulty Active Safety Control Module
• Open or shorted wiring harness
• Poor electrical connection
ASCM: Active Safety Control Module
OBD-II: On-Board Diagnostics, Second Generation
• U0100
• U0121
This code means that your car's computer is having trouble talking to one of the other parts of the car that it needs to communicate with.
The U0644 code indicates a loss of communication with a specific module in the vehicle.
U0644 is a communication fault code that signifies a loss of communication with the Active Safety Control Module (ASCM). This means the main computer isn't receiving or sending information to this module properly.
• Check for other codes and clear them to see if U0644 returns.
• Inspect the wiring and connectors to the ASCM.
• Test the ASCM for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the Active Safety Control Module if faulty.
• Update the vehicle's software if necessary.
• OBD-II scanner
• Multimeter
• Wiring diagram
$100 - $500
Moderate
• Toyota Camry
• Ford F-150
• Chevrolet Silverado
• Regularly inspect vehicle wiring for damage.
• Ensure all software updates are performed.
• Avoid exposing vehicle electronics to moisture.
Communication Issue
• Have the vehicle inspected by a professional if you notice any warning lights.
• Do not ignore the issue, as it could affect vehicle safety features.
Check with your vehicle manufacturer to see if the repair is covered under warranty.
U0644 has been reported in vehicles with complex safety systems, often due to connectivity issues.
Moderate – It's important to address this issue to ensure all safety features function properly.
Ignoring this code may lead to reduced safety feature performance, which could be dangerous.
• Vehicle in park with engine running
• All electrical systems on
The Active Safety Control Module is typically located under the dashboard or in the engine compartment.
Q: What does the Active Safety Control Module do?
A: It manages the vehicle's safety systems like airbags and stability control.
Q: Can I drive with a U0644 code?
A: It's not recommended, as some safety features may not work properly.
