Antilock Brake System - Pump Check Noise

Article No.
98-26-5

01/04/99

^ BRAKES - ANTI-LOCK - ABS NOISE

^ NOISE - ANTI-LOCK BRAKE SYSTEM (ABS) NOISE

FORD:
1998-99 CROWN VICTORIA, TAURUS

LINCOLN-MERCURY:
1998-99 CONTINENTAL, GRAND MARQUIS, SABLE, TOWN CAR

LIGHT TRUCK:
1998-99 WINDSTAR

ISSUE
Customers may complain of Anti-lock Brake System (ABS) or ABS/Traction Control (ABS/TC) pump check noise. The noise is sometimes perceived as coming from the engine, transmission, or steering areas. As part of normal operation, the ABS and ABS/TC strategies require a short cycling of the hydraulic control unit pump after each ignition start. This pump check results in a brief mechanical noise pulse and slight brake pedal vibration the first time the vehicle exceeds 16 km/h (10 mph) after each startup.

ACTION
This brief ABS pump check is normal operation of the ABS. Unless the noise persists with no brakes applied and/or the amber ABS light and/or traction control light remains lit or flashes, the system is functioning normally and should not be serviced. This should be explained to the customer with reference to the "Driving" section of his/her Owner Guide as part of the normal operation of the ABS system.

OTHER APPLICABLE ARTICLES: NONE
WARRANTY STATUS: INFORMATION ONLY
OASIS CODES: 301000, 303000, 497000, 597997, 702000, 702100