Some owners of 2010-2017 Buick Enclave vehicles might comment about a clunk/thump noise on acceleration once after each key cycle that might be mistaken as coming from the suspension or engine compartment.
Some owners of 2010-2017 Buick Enclave vehicles may comment about a clunk/thump noise on acceleration once after each key cycle that may be mistaken as coming from the suspension or engine compartment.
The noise may be caused by the second phase power-up self-test of the anti-brake system (ABS). This self-test begins when the vehicle is driven at a speed greater than 9 mph and the EBCM has not detected any traction control/vehicle stability-related concerns. This phase of the power-up self-test may be heard or felt by the driver. The system solenoids and ABS pump motor are commanded ON and OFF to verify the proper operation and the EBCM verifies the ability to return the system to base braking in the event of a failure. The EBCM isolates all of the wheels by briefly closing the four isolation valves and occasionally the driver may detect this by experiencing a momentary hard pedal.
In most cases, the ABS self-test noise should be considered normal. If a particular vehicle exhibits a noise that is louder than a comparable vehicle, the brake lines should be inspected for contact with the underbody or lines contacting each other. If any contact is present, the lines should be isolated to minimize the noise produced by the ABS self-test.
Information for Technical Service Bulletins comes from ProDemand, Mitchell 1's auto repair information software for domestic and import vehicles. Headquartered in San Diego, Mitchell 1 has provided quality repair information solutions to the automotive industry since 1918.
Mike Mavrigian has written thousands of automotive technical magazine articles involving a variety ofspecialties, from engine building to wheel alignment, and has authored more than a dozen books that crisscross the automotive spectrum. Mike operates Birchwood Automotive, an Ohio shop that builds custom engines and performs vintage vehicle restorations. The shop also features a professional photo studio to document projects and to create images for articles and books.
