Mazda Tech Tip: Clunk/Bang On Initial Forward Take-Off – UnderhoodService

Mazda Tech Tip: Clunk/Bang On Initial Forward Take-Off

Some customers may report a slight clunk, bang or jolt from the front of the vehicle. This concern will most likely occur during the vehicle's first forward movement, and after the vehicle sits for a few hours and/or a cold soak. This is a normal operating noise of the Anti-Lock Brake System (ABS).

MODELS:
2007-2011 CX-7
2007-2011 CX-9
2006-2011 Miata/MX5
2007-2011 Mazda3
2006-2011 Mazda5
2007-2011 MazdaSpeed
2004-2011 RX-8

ISSUE:

Some customers may report a slight clunk, bang or jolt from the front of the vehicle. This concern will most likely occur during the vehicle’s first forward movement, and after the vehicle sits for a few hours and/or a cold soak. This is a normal operating noise of the Anti-Lock Brake System (ABS). Do not attempt any repairs.

If you encounter a customer complaint for this concern, explain that the noise comes from the ABS/TCS/DSC “Malfunction Detection Function” initial check. The initial check is a necessary function to ensure the normal operation of the ABS/TCS/DSC system.

This initial test function occurs during the vehicles first forward movement and when the vehicle reaches approximately 6.2 mph (10 km/h).

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